initial push with task5b done

.gitignore

@@ -0,0 +1,62 @@
+.metadata
+bin/
+tmp/
+*.tmp
+*.bak
+*.swp
+*~.nib
+local.properties
+.settings/
+.loadpath
+.recommenders
+.vscode
+
+# External tool builders
+.externalToolBuilders/
+
+# Locally stored "Eclipse launch configurations"
+*.launch
+
+# PyDev specific (Python IDE for Eclipse)
+*.pydevproject
+
+# CDT-specific (C/C++ Development Tooling)
+.cproject
+
+# CDT- autotools
+.autotools
+
+# Java annotation processor (APT)
+.factorypath
+
+# PDT-specific (PHP Development Tools)
+.buildpath
+
+# sbteclipse plugin
+.target
+
+# Tern plugin
+.tern-project
+
+# TeXlipse plugin
+.texlipse
+
+# STS (Spring Tool Suite)
+.springBeans
+
+# Code Recommenders
+.recommenders/
+
+# Annotation Processing
+.apt_generated/
+.apt_generated_test/
+
+# Scala IDE specific (Scala & Java development for Eclipse)
+.cache-main
+.scala_dependencies
+.worksheet
+
+# Uncomment this line if you wish to ignore the project description file.
+# Typically, this file would be tracked if it contains build/dependency configurations:
+#.project
+/.gradle/

.project

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>a5-triangle-tools</name>
+	<comment>Project a5-triangle-tools created by Buildship.</comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.buildship.core.gradleprojectbuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.buildship.core.gradleprojectnature</nature>
+	</natures>
+</projectDescription>

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2022 deryckb
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

Triangle.AbstractMachine.Disassembler/.gitignore

@@ -0,0 +1,3 @@
+/target/
+/.classpath
+/build/

Triangle.AbstractMachine.Disassembler/.project

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>Triangle.AbstractMachine.Disassembler</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.eclipse.buildship.core.gradleprojectbuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+		<nature>org.eclipse.buildship.core.gradleprojectnature</nature>
+	</natures>
+</projectDescription>

Triangle.AbstractMachine.Disassembler/build.gradle

@@ -0,0 +1,12 @@
+apply plugin: 'java'
+apply plugin: 'application'
+
+sourceCompatibility = 11
+
+dependencies {
+	implementation project(':Triangle.AbstractMachine')
+}
+
+application {
+	mainClass = 'Triangle.AbstractMachine.Disassembler'
+}

Triangle.AbstractMachine.Disassembler/pom.xml

@@ -0,0 +1,18 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <artifactId>triangle-disassembler</artifactId>
+  <parent>
+    <groupId>triangle.tools</groupId>
+    <artifactId>triangle-tools</artifactId>
+    <version>2.1</version>
+    <relativePath>../</relativePath>
+  </parent>
+  <dependencies>
+    <dependency>
+      <groupId>triangle.tools</groupId>
+      <artifactId>triangle-abstractmachine</artifactId>
+      <version>2.1</version>
+    </dependency>
+  </dependencies>
+</project>

Triangle.AbstractMachine.Disassembler/src/main/java/triangle/abstractMachine/Disassembler.java

@@ -0,0 +1,355 @@
+/*
+ * @(#)Disassembler.java                        
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractMachine;
+
+import java.io.DataInputStream;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+
+/**
+ * Disassembles the TAM code in the given file, and displays the instructions on
+ * standard output.
+ *
+ * For example:
+ *
+ * <pre>
+ *   java TAM.Disassembler obj.tam
+ * </pre>
+ *
+ * <p>
+ * Copyright 1991 David A. Watt, University of Glasgow<br>
+ * Copyright 1998 Deryck F. Brown, The Robert Gordon University<br>
+ * </p>
+ *
+ */
+
+public class Disassembler {
+
+	static String objectName;
+
+	static int CT;
+
+	/**
+	 * Writes the r-field of an instruction in the form "l<I>reg</I>r", where l and
+	 * r are the bracket characters to use.
+	 *
+	 * @param leftbracket  the character to print before the register.
+	 * @param r            the number of the register.
+	 * @param rightbracket the character to print after the register.
+	 */
+	private static void writeR(char leftbracket, Register r, char rightbracket) {
+
+		System.out.print(leftbracket);
+		System.out.print(r.toString());
+		System.out.print(rightbracket);
+	}
+
+	private static void writeR(char leftBracket, int r, char rightBracket) {
+		var register = Register.values()[r];
+		writeR(leftBracket, register, rightBracket);
+	}
+
+	/**
+	 * Writes a void n-field of an instruction.
+	 */
+	private static void blankN() {
+		System.out.print("      ");
+	}
+
+	// Writes the n-field of an instruction.
+	/**
+	 * Writes the n-field of an instruction in the form "(n)".
+	 *
+	 * @param n the integer to write.
+	 */
+	private static void writeN(int n) {
+		System.out.print("(" + n + ") ");
+		if (n < 10) {
+			System.out.print("  ");
+		} else if (n < 100) {
+			System.out.print(" ");
+		}
+	}
+
+	/**
+	 * Writes the d-field of an instruction.
+	 *
+	 * @param d the integer to write.
+	 */
+	private static void writeD(int d) {
+		System.out.print(d);
+	}
+
+	/**
+	 * Writes the name of primitive routine with relative address d.
+	 *
+	 * @param d the displacement of the primitive routine.
+	 */
+	private static void writePrimitive(int d) {
+		var primitive = Primitive.values()[d];
+		switch (primitive) {
+		case ID:
+			System.out.print("id      ");
+			break;
+		case NOT:
+			System.out.print("not     ");
+			break;
+		case AND:
+			System.out.print("and     ");
+			break;
+		case OR:
+			System.out.print("or      ");
+			break;
+		case SUCC:
+			System.out.print("succ    ");
+			break;
+		case PRED:
+			System.out.print("pred    ");
+			break;
+		case NEG:
+			System.out.print("neg     ");
+			break;
+		case ADD:
+			System.out.print("add     ");
+			break;
+		case SUB:
+			System.out.print("sub     ");
+			break;
+		case MULT:
+			System.out.print("mult    ");
+			break;
+		case DIV:
+			System.out.print("div     ");
+			break;
+		case MOD:
+			System.out.print("mod     ");
+			break;
+		case LT:
+			System.out.print("lt      ");
+			break;
+		case LE:
+			System.out.print("le      ");
+			break;
+		case GE:
+			System.out.print("ge      ");
+			break;
+		case GT:
+			System.out.print("gt      ");
+			break;
+		case EQ:
+			System.out.print("eq      ");
+			break;
+		case NE:
+			System.out.print("ne      ");
+			break;
+		case EOL:
+			System.out.print("eol     ");
+			break;
+		case EOF:
+			System.out.print("eof     ");
+			break;
+		case GET:
+			System.out.print("get     ");
+			break;
+		case PUT:
+			System.out.print("put     ");
+			break;
+		case GETEOL:
+			System.out.print("geteol  ");
+			break;
+		case PUTEOL:
+			System.out.print("puteol  ");
+			break;
+		case GETINT:
+			System.out.print("getint  ");
+			break;
+		case PUTINT:
+			System.out.print("putint  ");
+			break;
+		case NEW:
+			System.out.print("new     ");
+			break;
+		case DISPOSE:
+			System.out.print("dispose ");
+			break;
+		}
+	}
+
+	/**
+	 * Writes the given instruction in assembly-code format.
+	 *
+	 * @param instr the instruction to display.
+	 */
+	private static void writeInstruction(Instruction instr) {
+
+		switch (instr.opCode) {
+		case LOAD:
+			System.out.print("LOAD  ");
+			writeN(instr.length);
+			writeD(instr.operand);
+			writeR('[', instr.register, ']');
+			break;
+
+		case LOADA:
+			System.out.print("LOADA ");
+			blankN();
+			writeD(instr.operand);
+			writeR('[', instr.register, ']');
+			break;
+
+		case LOADI:
+			System.out.print("LOADI ");
+			writeN(instr.length);
+			break;
+
+		case LOADL:
+			System.out.print("LOADL ");
+			blankN();
+			writeD(instr.operand);
+			break;
+
+		case STORE:
+			System.out.print("STORE ");
+			writeN(instr.length);
+			writeD(instr.operand);
+			writeR('[', instr.register, ']');
+			break;
+
+		case STOREI:
+			System.out.print("STOREI");
+			writeN(instr.length);
+			break;
+
+		case CALL:
+			System.out.print("CALL  ");
+			if (instr.register == Register.PB) {
+				blankN();
+				writePrimitive(instr.operand);
+			} else {
+				writeR('(', instr.length, ')');
+				System.out.print("  ");
+				writeD(instr.operand);
+				writeR('[', instr.register, ']');
+			}
+			break;
+
+		case CALLI:
+			System.out.print("CALLI ");
+			break;
+
+		case RETURN:
+			System.out.print("RETURN");
+			writeN(instr.length);
+			writeD(instr.operand);
+			break;
+
+		case PUSH:
+			System.out.print("PUSH  ");
+			blankN();
+			writeD(instr.operand);
+			break;
+
+		case POP:
+			System.out.print("POP   ");
+			writeN(instr.length);
+			writeD(instr.operand);
+			break;
+
+		case JUMP:
+			System.out.print("JUMP  ");
+			blankN();
+			writeD(instr.operand);
+			writeR('[', instr.register, ']');
+			break;
+
+		case JUMPI:
+			System.out.print("JUMPI ");
+			break;
+
+		case JUMPIF:
+			System.out.print("JUMPIF");
+			writeN(instr.length);
+			writeD(instr.operand);
+			writeR('[', instr.register, ']');
+			break;
+
+		case HALT:
+			System.out.print("HALT  ");
+		}
+	}
+
+	/**
+	 * Writes all instructions of the program in code store.
+	 */
+	private static void disassembleProgram() {
+		for (int addr = Machine.CB; addr < CT; addr++) {
+			System.out.print(addr + ":  ");
+			writeInstruction(Machine.code[addr]);
+			System.out.println();
+		}
+	}
+
+	// LOADING
+
+	/**
+	 * Loads the TAM object program into code store from the named file.
+	 *
+	 * @param objectName the name of the file containing the program.
+	 */
+	static void loadObjectProgram(String objectName) {
+
+		var finished = false;
+
+		try (var objectFile = new FileInputStream(objectName)) {
+			var objectStream = new DataInputStream(objectFile);
+			var addr = Machine.CB;
+			while (!finished) {
+				Machine.code[addr] = Instruction.read(objectStream);
+				if (Machine.code[addr] == null) {
+					finished = true;
+				} else {
+					addr = addr + 1;
+				}
+			}
+			CT = addr;
+		} catch (FileNotFoundException s) {
+			CT = Machine.CB;
+			System.err.println("Error opening object file: " + s);
+		} catch (IOException s) {
+			CT = Machine.CB;
+			System.err.println("Error reading object file: " + s);
+		}
+	}
+
+	// DISASSEMBLE
+
+	public static void main(String[] args) {
+		System.out.println("********** TAM Disassembler (Sun Version 2.1) **********");
+
+		if (args.length == 1) {
+			objectName = args[0];
+		} else {
+			objectName = "obj.tam";
+		}
+
+		loadObjectProgram(objectName);
+		disassembleProgram();
+	}
+}

Triangle.AbstractMachine.Interpreter/.gitignore

@@ -0,0 +1,3 @@
+/target/
+/.classpath
+/build/

Triangle.AbstractMachine.Interpreter/.project

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>Triangle.AbstractMachine.Interpreter</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.eclipse.buildship.core.gradleprojectbuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+		<nature>org.eclipse.buildship.core.gradleprojectnature</nature>
+	</natures>
+</projectDescription>

Triangle.AbstractMachine.Interpreter/build.gradle

@@ -0,0 +1,12 @@
+apply plugin: 'java'
+apply plugin: 'application'
+
+sourceCompatibility = 11
+
+dependencies {
+	implementation project(':Triangle.AbstractMachine')
+}
+
+application {
+	mainClass = 'Triangle.AbstractMachine.Interpreter'
+}

Triangle.AbstractMachine.Interpreter/pom.xml

@@ -0,0 +1,18 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <artifactId>triangle-interpreter</artifactId>
+  <parent>
+    <groupId>triangle.tools</groupId>
+    <artifactId>triangle-tools</artifactId>
+    <version>2.1</version>
+    <relativePath>../</relativePath>
+  </parent>
+  <dependencies>
+    <dependency>
+      <groupId>triangle.tools</groupId>
+      <artifactId>triangle-abstractmachine</artifactId>
+      <version>2.1</version>
+    </dependency>
+  </dependencies>
+</project>

Triangle.AbstractMachine.Interpreter/src/main/java/triangle/abstractMachine/Interpreter.java

@@ -0,0 +1,649 @@
+/*
+ * @(#)Interpreter.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractMachine;
+
+import java.io.DataInputStream;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+
+public class Interpreter {
+
+	static long startTimeNanos = 0;
+	
+	static String objectName;
+
+	// DATA STORE
+
+	static int[] data = new int[1024];
+
+	// DATA STORE REGISTERS AND OTHER REGISTERS
+
+	final static int CB = 0, SB = 0, HB = 1024; // = upper bound of data array + 1
+
+	static int CT, CP, ST, HT, LB, status;
+
+	// status values
+	final static int running = 0, halted = 1, failedDataStoreFull = 2, failedInvalidCodeAddress = 3,
+			failedInvalidInstruction = 4, failedOverflow = 5, failedZeroDivide = 6, failedIOError = 7;
+
+	static long accumulator;
+
+	static int content(int r) {
+		var register = Register.values()[r];
+		return content(register);
+	}
+
+	static int content(Register r) {
+		// Returns the current content of register r,
+		// even if r is one of the pseudo-registers L1..L6.
+
+		switch (r) {
+		case CB:
+			return CB;
+		case CT:
+			return CT;
+		case PB:
+			return Machine.PB;
+		case PT:
+			return Machine.PT;
+		case SB:
+			return SB;
+		case ST:
+			return ST;
+		case HB:
+			return HB;
+		case HT:
+			return HT;
+		case LB:
+			return LB;
+		case L1:
+			return data[LB];
+		case L2:
+			return data[data[LB]];
+		case L3:
+			return data[data[data[LB]]];
+		case L4:
+			return data[data[data[data[LB]]]];
+		case L5:
+			return data[data[data[data[data[LB]]]]];
+		case L6:
+			return data[data[data[data[data[data[LB]]]]]];
+		case CP:
+			return CP;
+		default:
+			return 0;
+		}
+	}
+
+	// PROGRAM STATUS
+
+	static void dump() {
+		// Writes a summary of the machine state.
+
+		System.out.println("");
+		System.out.println("State of data store and registers:");
+		System.out.println("");
+		if (HT == HB) {
+			System.out.println("            |--------|          (heap is empty)");
+		} else {
+			System.out.println("       HB-->");
+			System.out.println("            |--------|");
+			for (var addr = HB - 1; addr >= HT; addr--) {
+				System.out.print(addr + ":");
+				if (addr == HT) {
+					System.out.print(" HT-->");
+				} else {
+					System.out.print("      ");
+				}
+				System.out.println("|" + data[addr] + "|");
+			}
+			System.out.println("            |--------|");
+		}
+		System.out.println("            |////////|");
+		System.out.println("            |////////|");
+		if (ST == SB) {
+			System.out.println("            |--------|          (stack is empty)");
+		} else {
+			var dynamicLink = LB;
+			var staticLink = LB;
+			var localRegNum = Register.LB;
+			System.out.println("      ST--> |////////|");
+			System.out.println("            |--------|");
+			for (var addr = ST - 1; addr >= SB; addr--) {
+				System.out.print(addr + ":");
+				if (addr == SB) {
+					System.out.print(" SB-->");
+				} else if (addr == staticLink) {
+					switch (localRegNum) {
+					case LB:
+						System.out.print(" LB-->");
+						break;
+					case L1:
+						System.out.print(" L1-->");
+						break;
+					case L2:
+						System.out.print(" L2-->");
+						break;
+					case L3:
+						System.out.print(" L3-->");
+						break;
+					case L4:
+						System.out.print(" L4-->");
+						break;
+					case L5:
+						System.out.print(" L5-->");
+						break;
+					case L6:
+						System.out.print(" L6-->");
+						break;
+					default:
+						break;
+					}
+					staticLink = data[addr];
+					localRegNum = Register.values()[localRegNum.ordinal() + 1];
+				} else {
+					System.out.print("      ");
+				}
+				if (addr == dynamicLink && dynamicLink != SB) {
+					System.out.print("|SL=" + data[addr] + "|");
+				} else if (addr == dynamicLink + 1 && dynamicLink != SB) {
+					System.out.print("|DL=" + data[addr] + "|");
+				} else if (addr == dynamicLink + 2 && dynamicLink != SB) {
+					System.out.print("|RA=" + data[addr] + "|");
+				} else {
+					System.out.print("|" + data[addr] + "|");
+				}
+				System.out.println("");
+				if (addr == dynamicLink) {
+					System.out.println("            |--------|");
+					dynamicLink = data[addr + 1];
+				}
+			}
+		}
+		System.out.println("");
+	}
+
+	static void showStatus() {
+		// Writes an indication of whether and why the program has terminated.
+		System.out.println("");
+		switch (status) {
+		case running:
+			System.out.println("Program is running.");
+			break;
+		case halted:
+			System.out.println("Program has halted normally.");
+			System.out.println("Total execution time (ns): " + (System.nanoTime() - startTimeNanos));
+			break;
+		case failedDataStoreFull:
+			System.out.println("Program has failed due to exhaustion of Data Store.");
+			break;
+		case failedInvalidCodeAddress:
+			System.out.println("Program has failed due to an invalid code address.");
+			break;
+		case failedInvalidInstruction:
+			System.out.println("Program has failed due to an invalid instruction.");
+			break;
+		case failedOverflow:
+			System.out.println("Program has failed due to overflow.");
+			break;
+		case failedZeroDivide:
+			System.out.println("Program has failed due to division by zero.");
+			break;
+		case failedIOError:
+			System.out.println("Program has failed due to an IO error.");
+			break;
+		}
+		if (status != halted) {
+			dump();
+		}
+	}
+
+	// INTERPRETATION
+
+	static void checkSpace(int spaceNeeded) {
+		// Signals failure if there is not enough space to expand the stack or
+		// heap by spaceNeeded.
+
+		if (HT - ST < spaceNeeded) {
+			status = failedDataStoreFull;
+		}
+	}
+
+	static boolean isTrue(int datum) {
+		// Tests whether the given datum represents true.
+		return (datum == Machine.trueRep);
+	}
+
+	static boolean equal(int size, int addr1, int addr2) {
+		// Tests whether two multi-word objects are equal, given their common
+		// size and their base addresses.
+
+		boolean eq;
+		int index;
+
+		eq = true;
+		index = 0;
+		while (eq && (index < size)) {
+			if (data[addr1 + index] == data[addr2 + index]) {
+				index = index + 1;
+			} else {
+				eq = false;
+			}
+		}
+
+		return eq;
+	}
+
+	static int overflowChecked(long datum) {
+		// Signals failure if the datum is too large to fit into a single word,
+		// otherwise returns the datum as a single word.
+
+		if ((-Machine.maxintRep <= datum) && (datum <= Machine.maxintRep)) {
+			return (int) datum;
+		} else {
+			status = failedOverflow;
+			return 0;
+		}
+	}
+
+	static int toInt(boolean b) {
+		return b ? Machine.trueRep : Machine.falseRep;
+	}
+
+	static int currentChar;
+
+	static int readInt() throws java.io.IOException {
+		int temp = 0;
+		int sign = 1;
+
+		do {
+			currentChar = System.in.read();
+		} while (Character.isWhitespace((char) currentChar));
+
+		if ((currentChar == '-') || (currentChar == '+')) {
+			do {
+				sign = (currentChar == '-') ? -1 : 1;
+				currentChar = System.in.read();
+			} while ((currentChar == '-') || currentChar == '+');
+		}
+
+		if (Character.isDigit((char) currentChar)) {
+			do {
+				temp = temp * 10 + (currentChar - '0');
+				currentChar = System.in.read();
+			} while (Character.isDigit((char) currentChar));
+		}
+
+		return sign * temp;
+	}
+
+	static void callPrimitive(int primitiveDisplacement) {
+		// Invokes the given primitive routine.
+
+		int addr, size;
+		char ch;
+
+		var primitive = Primitive.values()[primitiveDisplacement];
+		switch (primitive) {
+		case ID:
+			break; // nothing to be done
+		case NOT:
+			data[ST - 1] = toInt(!isTrue(data[ST - 1]));
+			break;
+		case AND:
+			ST = ST - 1;
+			data[ST - 1] = toInt(isTrue(data[ST - 1]) & isTrue(data[ST]));
+			break;
+		case OR:
+			ST = ST - 1;
+			data[ST - 1] = toInt(isTrue(data[ST - 1]) | isTrue(data[ST]));
+			break;
+		case SUCC:
+			data[ST - 1] = overflowChecked(data[ST - 1] + 1);
+			break;
+		case PRED:
+			data[ST - 1] = overflowChecked(data[ST - 1] - 1);
+			break;
+		case NEG:
+			data[ST - 1] = -data[ST - 1];
+			break;
+		case ADD:
+			ST = ST - 1;
+			accumulator = data[ST - 1];
+			data[ST - 1] = overflowChecked(accumulator + data[ST]);
+			break;
+		case SUB:
+			ST = ST - 1;
+			accumulator = data[ST - 1];
+			data[ST - 1] = overflowChecked(accumulator - data[ST]);
+			break;
+		case MULT:
+			ST = ST - 1;
+			accumulator = data[ST - 1];
+			data[ST - 1] = overflowChecked(accumulator * data[ST]);
+			break;
+		case DIV:
+			ST = ST - 1;
+			accumulator = data[ST - 1];
+			if (data[ST] != 0) {
+				data[ST - 1] = (int) (accumulator / data[ST]);
+			} else {
+				status = failedZeroDivide;
+			}
+			break;
+		case MOD:
+			ST = ST - 1;
+			accumulator = data[ST - 1];
+			if (data[ST] != 0) {
+				data[ST - 1] = (int) (accumulator % data[ST]);
+			} else {
+				status = failedZeroDivide;
+			}
+			break;
+		case LT:
+			ST = ST - 1;
+			data[ST - 1] = toInt(data[ST - 1] < data[ST]);
+			break;
+		case LE:
+			ST = ST - 1;
+			data[ST - 1] = toInt(data[ST - 1] <= data[ST]);
+			break;
+		case GE:
+			ST = ST - 1;
+			data[ST - 1] = toInt(data[ST - 1] >= data[ST]);
+			break;
+		case GT:
+			ST = ST - 1;
+			data[ST - 1] = toInt(data[ST - 1] > data[ST]);
+			break;
+		case EQ:
+			size = data[ST - 1]; // size of each comparand
+			ST = ST - 2 * size;
+			data[ST - 1] = toInt(equal(size, ST - 1, ST - 1 + size));
+			break;
+		case NE:
+			size = data[ST - 1]; // size of each comparand
+			ST = ST - 2 * size;
+			data[ST - 1] = toInt(!equal(size, ST - 1, ST - 1 + size));
+			break;
+		case EOL:
+			data[ST] = toInt(currentChar == '\n');
+			ST = ST + 1;
+			break;
+		case EOF:
+			data[ST] = toInt(currentChar == -1);
+			ST = ST + 1;
+			break;
+		case GET:
+			ST = ST - 1;
+			addr = data[ST];
+			try {
+				currentChar = System.in.read();
+			} catch (java.io.IOException s) {
+				status = failedIOError;
+			}
+			data[addr] = currentChar;
+			break;
+		case PUT:
+			ST = ST - 1;
+			ch = (char) data[ST];
+			System.out.print(ch);
+			break;
+		case GETEOL:
+			try {
+				while ((currentChar = System.in.read()) != '\n')
+					;
+			} catch (java.io.IOException s) {
+				status = failedIOError;
+			}
+			break;
+		case PUTEOL:
+			System.out.println("");
+			break;
+		case GETINT:
+			ST = ST - 1;
+			addr = data[ST];
+			try {
+				accumulator = readInt();
+			} catch (java.io.IOException s) {
+				status = failedIOError;
+			}
+			data[addr] = (int) accumulator;
+			break;
+		case PUTINT:
+			ST = ST - 1;
+			accumulator = data[ST];
+			System.out.print(accumulator);
+			break;
+		case NEW:
+			size = data[ST - 1];
+			checkSpace(size);
+			HT = HT - size;
+			data[ST - 1] = HT;
+			break;
+		case DISPOSE:
+			ST = ST - 1; // no action taken at present
+			break;
+		}
+	}
+
+	static void interpretProgram() {
+		// Runs the program in code store.
+
+		Instruction currentInstr;
+
+		// Initialize registers ...
+		ST = SB;
+		HT = HB;
+		LB = SB;
+		CP = CB;
+		status = running;
+		do {
+			// Fetch instruction ...
+			currentInstr = Machine.code[CP];
+			// Decode instruction ...
+			var op = currentInstr.opCode;
+			var r = currentInstr.register;
+			var n = currentInstr.length;
+			var d = currentInstr.operand;
+			int addr;
+
+			// Execute instruction ...
+			switch (op) {
+			case LOAD:
+				addr = d + content(r);
+				checkSpace(n);
+				for (var index = 0; index < n; index++) {
+					data[ST + index] = data[addr + index];
+				}
+				ST = ST + n;
+				CP = CP + 1;
+				break;
+			case LOADA:
+				addr = d + content(r);
+				checkSpace(1);
+				data[ST] = addr;
+				ST = ST + 1;
+				CP = CP + 1;
+				break;
+			case LOADI:
+				ST = ST - 1;
+				addr = data[ST];
+				checkSpace(n);
+				for (var index = 0; index < n; index++) {
+					data[ST + index] = data[addr + index];
+				}
+				ST = ST + n;
+				CP = CP + 1;
+				break;
+			case LOADL:
+				checkSpace(1);
+				data[ST] = d;
+				ST = ST + 1;
+				CP = CP + 1;
+				break;
+			case STORE:
+				addr = d + content(r);
+				ST = ST - n;
+				for (var index = 0; index < n; index++) {
+					data[addr + index] = data[ST + index];
+				}
+				CP = CP + 1;
+				break;
+			case STOREI:
+				ST = ST - 1;
+				addr = data[ST];
+				ST = ST - n;
+				for (var index = 0; index < n; index++) {
+					data[addr + index] = data[ST + index];
+				}
+				CP = CP + 1;
+				break;
+			case CALL:
+				addr = d + content(r);
+				if (addr >= Machine.PB) {
+					callPrimitive(addr - Machine.PB);
+					CP = CP + 1;
+				} else {
+					checkSpace(3);
+					if (0 <= n && n <= 15) {
+						data[ST] = content(n); // static link
+					} else {
+						status = failedInvalidInstruction;
+					}
+					data[ST + 1] = LB; // dynamic link
+					data[ST + 2] = CP + 1; // return address
+					LB = ST;
+					ST = ST + 3;
+					CP = addr;
+				}
+				break;
+			case CALLI:
+				ST = ST - 2;
+				addr = data[ST + 1];
+				if (addr >= Machine.PB) {
+					callPrimitive(addr - Machine.PB);
+					CP = CP + 1;
+				} else {
+					// data[ST] = static link already
+					data[ST + 1] = LB; // dynamic link
+					data[ST + 2] = CP + 1; // return address
+					LB = ST;
+					ST = ST + 3;
+					CP = addr;
+				}
+				break;
+			case RETURN:
+				addr = LB - d;
+				CP = data[LB + 2];
+				LB = data[LB + 1];
+				ST = ST - n;
+				for (var index = 0; index < n; index++) {
+					data[addr + index] = data[ST + index];
+				}
+				ST = addr + n;
+				break;
+			case PUSH:
+				checkSpace(d);
+				ST = ST + d;
+				CP = CP + 1;
+				break;
+			case POP:
+				addr = ST - n - d;
+				ST = ST - n;
+				for (var index = 0; index < n; index++) {
+					data[addr + index] = data[ST + index];
+				}
+				ST = addr + n;
+				CP = CP + 1;
+				break;
+			case JUMP:
+				CP = d + content(r);
+				break;
+			case JUMPI:
+				ST = ST - 1;
+				CP = data[ST];
+				break;
+			case JUMPIF:
+				ST = ST - 1;
+				if (data[ST] == n) {
+					CP = d + content(r);
+				} else {
+					CP = CP + 1;
+				}
+				break;
+			case HALT:
+				status = halted;
+				break;
+			}
+			if (CP < CB || CP >= CT) {
+				status = failedInvalidCodeAddress;
+			}
+		} while (status == running);
+	}
+
+	// LOADING
+
+	static void loadObjectProgram(String objectName) {
+		// Loads the TAM object program into code store from the named file.
+
+		boolean finished = false;
+
+		try (var objectFile = new FileInputStream(objectName)) {
+			var objectStream = new DataInputStream(objectFile);
+
+			var addr = Machine.CB;
+			while (!finished) {
+				Machine.code[addr] = Instruction.read(objectStream);
+				if (Machine.code[addr] == null) {
+					finished = true;
+				} else {
+					addr = addr + 1;
+				}
+			}
+			CT = addr;
+		} catch (FileNotFoundException s) {
+			CT = CB;
+			System.err.println("Error opening object file: " + s);
+		} catch (IOException s) {
+			CT = CB;
+			System.err.println("Error reading object file: " + s);
+		}
+	}
+
+	// RUNNING
+
+	public static void main(String[] args) {
+		System.out.println("********** TAM Interpreter (Java Version 2.1) **********");
+
+		if (args.length == 1) {
+			objectName = args[0];
+		} else {
+			objectName = "obj.tam";
+		}
+
+		loadObjectProgram(objectName);
+		if (CT != CB) {
+			startTimeNanos = System.nanoTime();
+			interpretProgram();
+			showStatus();
+		}
+	}
+}

Triangle.AbstractMachine/.gitignore

@@ -0,0 +1,3 @@
+/target/
+/.classpath
+/build/

Triangle.AbstractMachine/.project

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>Triangle.AbstractMachine</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.eclipse.buildship.core.gradleprojectbuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+		<nature>org.eclipse.buildship.core.gradleprojectnature</nature>
+	</natures>
+</projectDescription>

Triangle.AbstractMachine/build.gradle

@@ -0,0 +1,4 @@
+apply plugin: 'java-library'
+apply plugin: 'eclipse'
+
+sourceCompatibility = 11

Triangle.AbstractMachine/pom.xml

@@ -0,0 +1,12 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>triangle-abstractmachine</artifactId>
+    <packaging>jar</packaging>
+    <parent>
+        <groupId>triangle.tools</groupId>
+        <artifactId>triangle-tools</artifactId>
+        <version>2.1</version>
+        <relativePath>../</relativePath>
+    </parent>
+</project>

Triangle.AbstractMachine/src/main/java/triangle/abstractMachine/Instruction.java

@@ -0,0 +1,71 @@
+/*
+ * @(#)Instruction.java                        
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractMachine;
+
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.EOFException;
+import java.io.IOException;
+
+public class Instruction {
+
+	// Java has no type synonyms, so the following representations are
+	// assumed:
+	//
+	// type
+	// OpCode = 0..15; {4 bits unsigned}
+	// Length = 0..255; {8 bits unsigned}
+	// Operand = -32767..+32767; {16 bits signed}
+
+	// Represents TAM instructions.
+	final OpCode opCode;
+	final Register register;
+	final int length;
+	int operand; // Not final to allow for patching jump address
+
+	public Instruction(OpCode opcode, Register register, int length, int operand) {
+		this.opCode = opcode;
+		this.register = register;
+		this.length = length;
+		this.operand = operand;
+	}
+
+	public void setOperand(int operand) {
+		this.operand = operand;
+	}
+	
+	public void write(DataOutputStream output) throws IOException {
+		output.writeInt(opCode.ordinal());
+		output.writeInt(register.ordinal());
+		output.writeInt(length);
+		output.writeInt(operand);
+	}
+
+	public static Instruction read(DataInputStream input) throws IOException {
+		try {
+			var opCode = OpCode.values()[input.readInt()];
+			var register = Register.values()[input.readInt()];
+			var length = input.readInt();
+			var operand = input.readInt();
+			return new Instruction(opCode, register, length, operand);
+		} catch (EOFException s) {
+			return null;
+		}
+	}
+}

Triangle.AbstractMachine/src/main/java/triangle/abstractMachine/Machine.java

@@ -0,0 +1,58 @@
+/*
+ * @(#)Machine.java                        
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractMachine;
+
+public final class Machine {
+
+	public final static int maxRoutineLevel = 7;
+
+	// WORDS AND ADDRESSES
+
+	// Java has no type synonyms, so the following representations are
+	// assumed:
+	//
+	// type
+	// Word = -32767..+32767; {16 bits signed}
+	// DoubleWord = -2147483648..+2147483647; {32 bits signed}
+	// CodeAddress = 0..+32767; {15 bits unsigned}
+	// DataAddress = 0..+32767; {15 bits unsigned}
+
+	// INSTRUCTIONS
+
+	// CODE STORE
+
+	public static Instruction[] code = new Instruction[1024];
+
+	// CODE STORE REGISTERS
+
+	public final static int CB = 0, PB = 1024, // = upper bound of code array + 1
+			PT = 1052; // = PB + 28
+
+	// REGISTER NUMBERS
+
+	// DATA REPRESENTATION
+
+	public final static int booleanSize = 1, characterSize = 1, integerSize = 1, addressSize = 1,
+			closureSize = 2 * addressSize,
+
+			linkDataSize = 3 * addressSize,
+
+			falseRep = 0, trueRep = 1, maxintRep = 32767;
+
+}

Triangle.AbstractMachine/src/main/java/triangle/abstractMachine/OpCode.java

@@ -0,0 +1,5 @@
+package triangle.abstractMachine;
+
+public enum OpCode {
+	LOAD, LOADA, LOADI, LOADL, STORE, STOREI, CALL, CALLI, RETURN, NOP, PUSH, POP, JUMP, JUMPI, JUMPIF, HALT
+}

Triangle.AbstractMachine/src/main/java/triangle/abstractMachine/Primitive.java

@@ -0,0 +1,6 @@
+package triangle.abstractMachine;
+
+public enum Primitive {
+	ID, NOT, AND, OR, SUCC, PRED, NEG, ADD, SUB, MULT, DIV, MOD, LT, LE, GE, GT, EQ, NE, EOL, EOF, GET, PUT, GETEOL,
+	PUTEOL, GETINT, PUTINT, NEW, DISPOSE
+}

Triangle.AbstractMachine/src/main/java/triangle/abstractMachine/Register.java

@@ -0,0 +1,5 @@
+package triangle.abstractMachine;
+
+public enum Register {
+	CB, CT, PB, PT, SB, ST, HB, HT, LB, L1, L2, L3, L4, L5, L6, CP
+}

Triangle.Compiler/.gitignore

@@ -0,0 +1,4 @@
+/target/
+/.classpath
+/.editorconfig
+/build/

Triangle.Compiler/.project

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>Triangle.Compiler</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.eclipse.buildship.core.gradleprojectbuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+		<nature>org.eclipse.buildship.core.gradleprojectnature</nature>
+	</natures>
+</projectDescription>

Triangle.Compiler/build.gradle

@@ -0,0 +1,24 @@
+apply plugin: 'java'
+apply plugin: 'application'
+
+sourceCompatibility = 11
+
+repositories {
+    mavenCentral()
+}
+
+
+dependencies {
+	implementation project(':Triangle.AbstractMachine')
+    // Task 2
+    implementation group: 'com.github.spullara.cli-parser', name: 'cli-parser', version: '1.1.5'
+    //
+	testImplementation group: 'junit', name: 'junit', version: '4.13.2'
+}
+
+application {
+	mainClass = 'Triangle.Compiler'
+}
+
+// allow access to programs for unit tests
+sourceSets.test.resources.srcDir file("$rootDir/programs")

Triangle.Compiler/pom.xml

@@ -0,0 +1,18 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <artifactId>triangle-compiler</artifactId>
+  <parent>
+    <groupId>triangle.tools</groupId>
+    <artifactId>triangle-tools</artifactId>
+    <version>2.1</version>
+    <relativePath>../</relativePath>
+  </parent>
+  <dependencies>
+    <dependency>
+      <groupId>triangle.tools</groupId>
+      <artifactId>triangle-abstractmachine</artifactId>
+      <version>2.1</version>
+    </dependency>
+  </dependencies>
+</project>

Triangle.Compiler/src/main/java/triangle/Compiler.java

@@ -0,0 +1,183 @@
+/*
+ * @(#)Compiler.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle;
+
+import triangle.abstractSyntaxTrees.Program;
+import triangle.codeGenerator.Emitter;
+import triangle.codeGenerator.Encoder;
+import triangle.contextualAnalyzer.Checker;
+import triangle.optimiser.ConstantFolder;
+import triangle.syntacticAnalyzer.Parser;
+import triangle.syntacticAnalyzer.Scanner;
+import triangle.syntacticAnalyzer.SourceFile;
+import triangle.treeDrawer.Drawer;
+
+// Task 2
+import com.sampullara.cli.Args;
+import com.sampullara.cli.Argument;
+
+/**
+ * The main driver class for the Triangle compiler.
+ *
+ * @version 2.1 7 Oct 2003
+ * @author Deryck F. Brown
+ */
+public class Compiler {
+
+	/** The filename for the object program, normally obj.tam. */
+	//static String objectNIame = "obj.tam";
+	//static boolean showTree = false;
+	//static boolean folding = false; //Better implementation below
+
+	private static Scanner scanner;
+	private static Parser parser;
+	private static Checker checker;
+	private static Encoder encoder;
+	private static Emitter emitter;
+	private static ErrorReporter reporter;
+	private static Drawer drawer;
+
+	/** The AST representing the source program. */
+	private static Program theAST;
+	
+	//Task 2
+	
+	@Argument(alias = "file", description="Name of file you want to compile", required = true)
+	static String sourceName = "";
+	
+	@Argument(alias = "obj", description="Object file name", required = true)
+	static String objectName = "obj.tam"; //default
+		
+	@Argument(alias = "tree", description="Enable AST")
+	static boolean showTree = false;
+		
+	@Argument(alias = "fold", description="Enable folding")
+	static boolean folding = false;
+		
+	@Argument(alias = "tfold", description="Enable AST after folding")
+	static boolean showTreeAfterFolding = false;
+	
+	//Task 5b
+	@Argument(alias = "stats", description="Enable stats (Char and Int Expr count)")
+	static boolean showStats = false;
+
+	/**
+	 * Compile the source program to TAM machine code.
+	 *
+	 * @param sourceName   		the name of the file containing the source program.
+	 * @param objectName   		the name of the file containing the object program.
+	 * @param showingAST   		true iff the AST is to be displayed after contextual
+	 *                     		analysis
+	 * @param showingTable 		true iff the object description details are to be
+	 *                     		displayed during code generation (not currently
+	 *                     		implemented).
+	 * @param showAfterFolding  show the AST after folding is complete
+	 * @param showStats 		show stats, these only (so far) inlcude char and int expressions
+	 * @return true iff the source program is free of compile-time errors, otherwise
+	 *         false.
+	 */
+	static boolean compileProgram(String sourceName, String objectName, boolean showingAST, boolean showingTable, boolean showAfterFolding, boolean showStats) {
+
+		System.out.println("********** " + "Triangle Compiler (Java Version 2.1)" + " **********");
+
+		System.out.println("Syntactic Analysis ...");
+		SourceFile source = SourceFile.ofPath(sourceName);
+
+		if (source == null) {
+			System.out.println("Can't access source file " + sourceName);
+			System.exit(1);
+		}
+
+		scanner = new Scanner(source);
+		reporter = new ErrorReporter(false);
+		parser = new Parser(scanner, reporter);
+		checker = new Checker(reporter);
+		emitter = new Emitter(reporter);
+		encoder = new Encoder(emitter, reporter);
+		drawer = new Drawer();
+		
+		//Task 5b
+		stats = new SummaryStats();
+
+		theAST = parser.parseProgram(); // 1st pass
+		if (reporter.getNumErrors() == 0) {
+			System.out.println("Contextual Analysis ...");
+			checker.check(theAST); // 2nd pass
+			
+			if (showingAST && !showAfterFolding) {
+				drawer.draw(theAST);
+			}
+			if (folding) {
+				theAST.visit(new ConstantFolder());
+				if (showingAST && showAfterFolding) {
+					drawer.draw(theAST); //if folding then also show tree
+				}
+			}
+
+			
+			if (reporter.getNumErrors() == 0) {
+				System.out.println("Code Generation ...");
+				encoder.encodeRun(theAST, showingTable); // 3rd pass
+			}
+		}
+
+		boolean successful = (reporter.getNumErrors() == 0);
+		if (successful) {
+			emitter.saveObjectProgram(objectName);
+			System.out.println("Compilation was successful.");
+			//Task 5b
+			System.out.println("[STATS] CharExpr: " + stats.getCharExprCount() + "!");
+			System.out.println("[STATS] IntExpr: " + stats.getIntExprCount() + "!");
+		} else {
+			System.out.println("Compilation was unsuccessful.");
+		}
+		return successful;
+	}
+
+	/**
+	 * Triangle compiler main program.
+	 *
+	 * @param args the only command-line argument to the program specifies the
+	 *             source filename.
+	 */
+	public static void main(String[] args) {
+
+		//Task 2
+		Args.parseOrExit(Compiler.class, args);
+		var compiledOK = compileProgram(Compiler.sourceName, Compiler.objectName, Compiler.showTree, false, Compiler.showTreeAfterFolding);
+
+		if (!showTree) {
+			System.exit(compiledOK ? 0 : 1);
+		}
+	}
+	
+	/* No longer needed */
+	private static void parseArgs(String[] args) {
+		for (String s : args) {
+			var sl = s.toLowerCase();
+			if (sl.equals("tree")) {
+				showTree = true;
+			} else if (sl.startsWith("-o=")) {
+				objectName = s.substring(3);
+			} else if (sl.equals("folding")) {
+				folding = true;
+			}
+		}
+	}
+}

Triangle.Compiler/src/main/java/triangle/ErrorReporter.java

@@ -0,0 +1,65 @@
+/*
+ * @(#)ErrorReporter.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle;
+
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class ErrorReporter {
+
+	private int numErrors;
+	
+	private boolean throwExceptions;
+
+	/**
+	 * @param throwExceptions if true, throw exceptions (good for unit tests) otherwise write to stdout
+	 */
+	public ErrorReporter(boolean throwExceptions) {
+		numErrors = 0;
+		this.throwExceptions = throwExceptions;
+	}
+
+	public void reportError(String message, String tokenName, SourcePosition pos) {
+
+		numErrors++;
+		
+		String s = ("ERROR: ");
+
+		for (int p = 0; p < message.length(); p++)
+			if (message.charAt(p) == '%')
+				s += tokenName;
+			else
+				s += message.charAt(p);
+		s += (" " + pos.start + ".." + pos.finish);
+		
+		if (throwExceptions) {
+			throw new RuntimeException(s);
+		} else {
+			System.out.println(s);
+		}
+		
+	}
+
+	public void reportRestriction(String message) {
+		System.out.println("RESTRICTION: " + message);
+	}
+	
+	public int getNumErrors() {
+		return numErrors;
+	}
+}

Triangle.Compiler/src/main/java/triangle/StdEnvironment.java

@@ -0,0 +1,50 @@
+/*
+ * @(#)StdEnvironment.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle;
+
+import triangle.abstractSyntaxTrees.declarations.BinaryOperatorDeclaration;
+import triangle.abstractSyntaxTrees.declarations.ConstDeclaration;
+import triangle.abstractSyntaxTrees.declarations.FuncDeclaration;
+import triangle.abstractSyntaxTrees.declarations.ProcDeclaration;
+import triangle.abstractSyntaxTrees.declarations.UnaryOperatorDeclaration;
+import triangle.abstractSyntaxTrees.types.TypeDeclaration;
+import triangle.abstractSyntaxTrees.types.TypeDenoter;
+
+public final class StdEnvironment {
+
+	// These are small ASTs representing standard types.
+
+	public static TypeDenoter booleanType, charType, integerType, anyType, errorType;
+
+	public static TypeDeclaration booleanDecl, charDecl, integerDecl;
+
+	// These are small ASTs representing "declarations" of standard entities.
+
+	public static ConstDeclaration falseDecl, trueDecl, maxintDecl;
+
+	public static UnaryOperatorDeclaration notDecl;
+
+	public static BinaryOperatorDeclaration andDecl, orDecl, addDecl, subtractDecl, multiplyDecl, divideDecl,
+			moduloDecl, equalDecl, unequalDecl, lessDecl, notlessDecl, greaterDecl, notgreaterDecl;
+
+	public static ProcDeclaration getDecl, putDecl, getintDecl, putintDecl, geteolDecl, puteolDecl;
+
+	public static FuncDeclaration chrDecl, ordDecl, eolDecl, eofDecl;
+
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/AbstractSyntaxTree.java

@@ -0,0 +1,38 @@
+/*
+ * @(#)AST.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees;
+
+import triangle.codeGenerator.entities.RuntimeEntity;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public abstract class AbstractSyntaxTree {
+
+	private final SourcePosition position;
+
+	public AbstractSyntaxTree(SourcePosition position) {
+		this.position = position;
+		entity = null;
+	}
+
+	public SourcePosition getPosition() {
+		return position;
+	}
+
+	public RuntimeEntity entity;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/Program.java

@@ -0,0 +1,41 @@
+/*
+ * @(#)Program.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees;
+
+import triangle.abstractSyntaxTrees.commands.Command;
+import triangle.abstractSyntaxTrees.visitors.ProgramVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class Program extends AbstractSyntaxTree {
+
+	public Program(Command cAST, SourcePosition position) {
+		super(position);
+		C = cAST;
+	}
+
+	public Command C;
+
+	public <TArg, TResult> TResult visit(ProgramVisitor<TArg, TResult> visitor, TArg arg) {
+		return visitor.visitProgram(this, arg);
+	}
+
+	public <TResult> TResult visit(ProgramVisitor<Void, TResult> visitor) {
+		return visit(visitor, null);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/actuals/ActualParameter.java

@@ -0,0 +1,36 @@
+/*
+ * @(#)ActualParameter.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.actuals;
+
+import triangle.abstractSyntaxTrees.AbstractSyntaxTree;
+import triangle.abstractSyntaxTrees.visitors.ActualParameterVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public abstract class ActualParameter extends AbstractSyntaxTree {
+
+	public ActualParameter(SourcePosition position) {
+		super(position);
+	}
+
+	public abstract <TArg, TResult> TResult visit(ActualParameterVisitor<TArg, TResult> visitor, TArg arg);
+
+	public <TArg, TResult> TResult visit(ActualParameterVisitor<TArg, TResult> visitor) {
+		return visit(visitor, null);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/actuals/ActualParameterSequence.java

@@ -0,0 +1,36 @@
+/*
+ * @(#)ActualParameterSequence.java               
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.actuals;
+
+import triangle.abstractSyntaxTrees.AbstractSyntaxTree;
+import triangle.abstractSyntaxTrees.visitors.ActualParameterSequenceVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public abstract class ActualParameterSequence extends AbstractSyntaxTree {
+
+	public ActualParameterSequence(SourcePosition position) {
+		super(position);
+	}
+
+	public abstract <TArg, TResult> TResult visit(ActualParameterSequenceVisitor<TArg, TResult> v, TArg arg);
+
+	public <TArg, TResult> TResult visit(ActualParameterSequenceVisitor<TArg, TResult> v) {
+		return visit(v, null);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/actuals/ConstActualParameter.java

@@ -0,0 +1,37 @@
+/*
+ * @(#)ConstActualParameter.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.actuals;
+
+import triangle.abstractSyntaxTrees.expressions.Expression;
+import triangle.abstractSyntaxTrees.visitors.ActualParameterVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class ConstActualParameter extends ActualParameter {
+
+	public ConstActualParameter(Expression eAST, SourcePosition position) {
+		super(position);
+		E = eAST;
+	}
+
+	public <TArg, TResult> TResult visit(ActualParameterVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitConstActualParameter(this, arg);
+	}
+
+	public Expression E;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/actuals/EmptyActualParameterSequence.java

@@ -0,0 +1,33 @@
+/*
+ * @(#)EmptyActualParameterSequence.java       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.actuals;
+
+import triangle.abstractSyntaxTrees.visitors.ActualParameterSequenceVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class EmptyActualParameterSequence extends ActualParameterSequence {
+
+	public EmptyActualParameterSequence(SourcePosition position) {
+		super(position);
+	}
+
+	public <TArg, TResult> TResult visit(ActualParameterSequenceVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitEmptyActualParameterSequence(this, arg);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/actuals/FuncActualParameter.java

@@ -0,0 +1,37 @@
+/*
+ * @(#)FuncActualParameter.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.actuals;
+
+import triangle.abstractSyntaxTrees.terminals.Identifier;
+import triangle.abstractSyntaxTrees.visitors.ActualParameterVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class FuncActualParameter extends ActualParameter {
+
+	public FuncActualParameter(Identifier iAST, SourcePosition position) {
+		super(position);
+		I = iAST;
+	}
+
+	public <TArg, TResult> TResult visit(ActualParameterVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitFuncActualParameter(this, arg);
+	}
+
+	public final Identifier I;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/actuals/MultipleActualParameterSequence.java

@@ -0,0 +1,39 @@
+/*
+ * @(#)MultipleActualParameterSequence.java               
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.actuals;
+
+import triangle.abstractSyntaxTrees.visitors.ActualParameterSequenceVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class MultipleActualParameterSequence extends ActualParameterSequence {
+
+	public MultipleActualParameterSequence(ActualParameter apAST, ActualParameterSequence apsAST,
+			SourcePosition position) {
+		super(position);
+		AP = apAST;
+		APS = apsAST;
+	}
+
+	public <TArg, TResult> TResult visit(ActualParameterSequenceVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitMultipleActualParameterSequence(this, arg);
+	}
+
+	public final ActualParameter AP;
+	public final ActualParameterSequence APS;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/actuals/ProcActualParameter.java

@@ -0,0 +1,37 @@
+/*
+ * @(#)ProcActualParameter.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.actuals;
+
+import triangle.abstractSyntaxTrees.terminals.Identifier;
+import triangle.abstractSyntaxTrees.visitors.ActualParameterVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class ProcActualParameter extends ActualParameter {
+
+	public ProcActualParameter(Identifier iAST, SourcePosition position) {
+		super(position);
+		I = iAST;
+	}
+
+	public <TArg, TResult> TResult visit(ActualParameterVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitProcActualParameter(this, arg);
+	}
+
+	public final Identifier I;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/actuals/SingleActualParameterSequence.java

@@ -0,0 +1,36 @@
+/*
+ * @(#)SingleActualParameterSequence.java               
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.actuals;
+
+import triangle.abstractSyntaxTrees.visitors.ActualParameterSequenceVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class SingleActualParameterSequence extends ActualParameterSequence {
+
+	public SingleActualParameterSequence(ActualParameter apAST, SourcePosition position) {
+		super(position);
+		AP = apAST;
+	}
+
+	public <TArg, TResult> TResult visit(ActualParameterSequenceVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitSingleActualParameterSequence(this, arg);
+	}
+
+	public final ActualParameter AP;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/actuals/VarActualParameter.java

@@ -0,0 +1,37 @@
+/*
+ * @(#)VarActualParameter.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.actuals;
+
+import triangle.abstractSyntaxTrees.visitors.ActualParameterVisitor;
+import triangle.abstractSyntaxTrees.vnames.Vname;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class VarActualParameter extends ActualParameter {
+
+	public VarActualParameter(Vname vAST, SourcePosition position) {
+		super(position);
+		V = vAST;
+	}
+
+	public <TArg, TResult> TResult visit(ActualParameterVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitVarActualParameter(this, arg);
+	}
+
+	public final Vname V;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/aggregates/ArrayAggregate.java

@@ -0,0 +1,39 @@
+/*
+ * @(#)ArrayAggregate.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.aggregates;
+
+import triangle.abstractSyntaxTrees.AbstractSyntaxTree;
+import triangle.abstractSyntaxTrees.visitors.ArrayAggregateVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public abstract class ArrayAggregate extends AbstractSyntaxTree {
+
+	public ArrayAggregate(SourcePosition position) {
+		super(position);
+		elemCount = 0;
+	}
+
+	public int elemCount;
+
+	public abstract <TArg, TResult> TResult visit(ArrayAggregateVisitor<TArg, TResult> visitor, TArg arg);
+
+	public <TArg, TResult> TResult visit(ArrayAggregateVisitor<TArg, TResult> visitor) {
+		return visit(visitor, null);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/aggregates/MultipleArrayAggregate.java

@@ -0,0 +1,39 @@
+/*
+ * @(#)MultipleArrayAggregate.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.aggregates;
+
+import triangle.abstractSyntaxTrees.expressions.Expression;
+import triangle.abstractSyntaxTrees.visitors.ArrayAggregateVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class MultipleArrayAggregate extends ArrayAggregate {
+
+	public MultipleArrayAggregate(Expression eAST, ArrayAggregate aaAST, SourcePosition position) {
+		super(position);
+		E = eAST;
+		AA = aaAST;
+	}
+
+	public <TArg, TResult> TResult visit(ArrayAggregateVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitMultipleArrayAggregate(this, arg);
+	}
+
+	public Expression E;
+	public final ArrayAggregate AA;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/aggregates/MultipleRecordAggregate.java

@@ -0,0 +1,42 @@
+/*
+ * @(#)MultipleRecordAggregate.java               
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.aggregates;
+
+import triangle.abstractSyntaxTrees.expressions.Expression;
+import triangle.abstractSyntaxTrees.terminals.Identifier;
+import triangle.abstractSyntaxTrees.visitors.RecordAggregateVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class MultipleRecordAggregate extends RecordAggregate {
+
+	public MultipleRecordAggregate(Identifier iAST, Expression eAST, RecordAggregate raAST, SourcePosition position) {
+		super(position);
+		I = iAST;
+		E = eAST;
+		RA = raAST;
+	}
+
+	public <TArg, TResult> TResult visit(RecordAggregateVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitMultipleRecordAggregate(this, arg);
+	}
+
+	public final Identifier I;
+	public Expression E;
+	public final RecordAggregate RA;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/aggregates/RecordAggregate.java

@@ -0,0 +1,40 @@
+/*
+ * @(#)RecordAggregate.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.aggregates;
+
+import triangle.abstractSyntaxTrees.AbstractSyntaxTree;
+import triangle.abstractSyntaxTrees.types.FieldTypeDenoter;
+import triangle.abstractSyntaxTrees.visitors.RecordAggregateVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public abstract class RecordAggregate extends AbstractSyntaxTree {
+
+	public RecordAggregate(SourcePosition position) {
+		super(position);
+		type = null;
+	}
+
+	public FieldTypeDenoter type;
+
+	public abstract <TArg, TResult> TResult visit(RecordAggregateVisitor<TArg, TResult> visitor, TArg arg);
+
+	public <TArg, TResult> TResult visit(RecordAggregateVisitor<TArg, TResult> visitor) {
+		return visit(visitor, null);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/aggregates/SingleArrayAggregate.java

@@ -0,0 +1,37 @@
+/*
+ * @(#)SingleArrayAggregate.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.aggregates;
+
+import triangle.abstractSyntaxTrees.expressions.Expression;
+import triangle.abstractSyntaxTrees.visitors.ArrayAggregateVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class SingleArrayAggregate extends ArrayAggregate {
+
+	public SingleArrayAggregate(Expression eAST, SourcePosition position) {
+		super(position);
+		E = eAST;
+	}
+
+	public <TArg, TResult> TResult visit(ArrayAggregateVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitSingleArrayAggregate(this, arg);
+	}
+
+	public Expression E;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/aggregates/SingleRecordAggregate.java

@@ -0,0 +1,40 @@
+/*
+ * @(#)SingleRecordAggregate.java               
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.aggregates;
+
+import triangle.abstractSyntaxTrees.expressions.Expression;
+import triangle.abstractSyntaxTrees.terminals.Identifier;
+import triangle.abstractSyntaxTrees.visitors.RecordAggregateVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class SingleRecordAggregate extends RecordAggregate {
+
+	public SingleRecordAggregate(Identifier iAST, Expression eAST, SourcePosition position) {
+		super(position);
+		I = iAST;
+		E = eAST;
+	}
+
+	public <TArg, TResult> TResult visit(RecordAggregateVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitSingleRecordAggregate(this, arg);
+	}
+
+	public final Identifier I;
+	public Expression E;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/commands/AssignCommand.java

@@ -0,0 +1,40 @@
+/*
+ * @(#)AssignCommand.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.commands;
+
+import triangle.abstractSyntaxTrees.expressions.Expression;
+import triangle.abstractSyntaxTrees.visitors.CommandVisitor;
+import triangle.abstractSyntaxTrees.vnames.Vname;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class AssignCommand extends Command {
+
+	public AssignCommand(Vname vAST, Expression eAST, SourcePosition position) {
+		super(position);
+		V = vAST;
+		E = eAST;
+	}
+
+	public <TArg, TResult> TResult visit(CommandVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitAssignCommand(this, arg);
+	}
+
+	public final Vname V;
+	public Expression E;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/commands/CallCommand.java

@@ -0,0 +1,40 @@
+/*
+ * @(#)CallCommand.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.commands;
+
+import triangle.abstractSyntaxTrees.actuals.ActualParameterSequence;
+import triangle.abstractSyntaxTrees.terminals.Identifier;
+import triangle.abstractSyntaxTrees.visitors.CommandVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class CallCommand extends Command {
+
+	public CallCommand(Identifier iAST, ActualParameterSequence apsAST, SourcePosition position) {
+		super(position);
+		I = iAST;
+		APS = apsAST;
+	}
+
+	public <TArg, TResult> TResult visit(CommandVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitCallCommand(this, arg);
+	}
+
+	public final Identifier I;
+	public final ActualParameterSequence APS;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/commands/Command.java

@@ -0,0 +1,36 @@
+/*
+ * @(#)Command.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.commands;
+
+import triangle.abstractSyntaxTrees.AbstractSyntaxTree;
+import triangle.abstractSyntaxTrees.visitors.CommandVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public abstract class Command extends AbstractSyntaxTree {
+
+	public Command(SourcePosition position) {
+		super(position);
+	}
+
+	public abstract <TArg, TResult> TResult visit(CommandVisitor<TArg, TResult> visitor, TArg arg);
+
+	public <TArg, TResult> TResult visit(CommandVisitor<TArg, TResult> visitor) {
+		return visit(visitor, null);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/commands/EmptyCommand.java

@@ -0,0 +1,33 @@
+/*
+ * @(#)EmptyCommand.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.commands;
+
+import triangle.abstractSyntaxTrees.visitors.CommandVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class EmptyCommand extends Command {
+
+	public EmptyCommand(SourcePosition position) {
+		super(position);
+	}
+
+	public <TArg, TResult> TResult visit(CommandVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitEmptyCommand(this, arg);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/commands/IfCommand.java

@@ -0,0 +1,40 @@
+/*
+ * @(#)IfCommand.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.commands;
+
+import triangle.abstractSyntaxTrees.expressions.Expression;
+import triangle.abstractSyntaxTrees.visitors.CommandVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class IfCommand extends Command {
+
+	public IfCommand(Expression eAST, Command c1AST, Command c2AST, SourcePosition position) {
+		super(position);
+		E = eAST;
+		C1 = c1AST;
+		C2 = c2AST;
+	}
+
+	public <TArg, TResult> TResult visit(CommandVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitIfCommand(this, arg);
+	}
+
+	public Expression E;
+	public final Command C1, C2;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/commands/LetCommand.java

@@ -0,0 +1,39 @@
+/*
+ * @(#)LetCommand.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.commands;
+
+import triangle.abstractSyntaxTrees.declarations.Declaration;
+import triangle.abstractSyntaxTrees.visitors.CommandVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class LetCommand extends Command {
+
+	public LetCommand(Declaration dAST, Command cAST, SourcePosition position) {
+		super(position);
+		D = dAST;
+		C = cAST;
+	}
+
+	public <TArg, TResult> TResult visit(CommandVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitLetCommand(this, arg);
+	}
+
+	public final Declaration D;
+	public final Command C;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/commands/SequentialCommand.java

@@ -0,0 +1,37 @@
+/*
+ * @(#)SequentialCommand.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.commands;
+
+import triangle.abstractSyntaxTrees.visitors.CommandVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class SequentialCommand extends Command {
+
+	public SequentialCommand(Command c1AST, Command c2AST, SourcePosition position) {
+		super(position);
+		C1 = c1AST;
+		C2 = c2AST;
+	}
+
+	public <TArg, TResult> TResult visit(CommandVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitSequentialCommand(this, arg);
+	}
+
+	public final Command C1, C2;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/commands/WhileCommand.java

@@ -0,0 +1,39 @@
+/*
+ * @(#)WhileCommand.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.commands;
+
+import triangle.abstractSyntaxTrees.expressions.Expression;
+import triangle.abstractSyntaxTrees.visitors.CommandVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class WhileCommand extends Command {
+
+	public WhileCommand(Expression eAST, Command cAST, SourcePosition position) {
+		super(position);
+		E = eAST;
+		C = cAST;
+	}
+
+	public <TArg, TResult> TResult visit(CommandVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitWhileCommand(this, arg);
+	}
+
+	public Expression E;
+	public final Command C;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/declarations/BinaryOperatorDeclaration.java

@@ -0,0 +1,43 @@
+/*
+ * @(#)BinaryOperatorDeclaration.java               
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.declarations;
+
+import triangle.abstractSyntaxTrees.terminals.Operator;
+import triangle.abstractSyntaxTrees.types.TypeDenoter;
+import triangle.abstractSyntaxTrees.visitors.DeclarationVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class BinaryOperatorDeclaration extends Declaration {
+
+	public BinaryOperatorDeclaration(Operator oAST, TypeDenoter arg1AST, TypeDenoter arg2AST, TypeDenoter resultAST,
+			SourcePosition position) {
+		super(position);
+		O = oAST;
+		ARG1 = arg1AST;
+		ARG2 = arg2AST;
+		RES = resultAST;
+	}
+
+	public <TArg, TResult> TResult visit(DeclarationVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitBinaryOperatorDeclaration(this, arg);
+	}
+
+	public final Operator O;
+	public final TypeDenoter ARG1, ARG2, RES;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/declarations/ConstDeclaration.java

@@ -0,0 +1,46 @@
+/*
+ * @(#)ConstDeclaration.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.declarations;
+
+import triangle.abstractSyntaxTrees.expressions.Expression;
+import triangle.abstractSyntaxTrees.terminals.Identifier;
+import triangle.abstractSyntaxTrees.types.TypeDenoter;
+import triangle.abstractSyntaxTrees.visitors.DeclarationVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class ConstDeclaration extends Declaration implements ConstantDeclaration {
+
+	public ConstDeclaration(Identifier iAST, Expression eAST, SourcePosition position) {
+		super(position);
+		I = iAST;
+		E = eAST;
+	}
+
+	@Override
+	public TypeDenoter getType() {
+		return E.type;
+	}
+	
+	public <TArg, TResult> TResult visit(DeclarationVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitConstDeclaration(this, arg);
+	}
+
+	public final Identifier I;
+	public Expression E;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/declarations/ConstantDeclaration.java

@@ -0,0 +1,9 @@
+package triangle.abstractSyntaxTrees.declarations;
+
+import triangle.abstractSyntaxTrees.types.TypeDenoter;
+
+public interface ConstantDeclaration {
+
+	TypeDenoter getType();
+	
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/declarations/Declaration.java

@@ -0,0 +1,39 @@
+/*
+ * @(#)Declaration.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.declarations;
+
+import triangle.abstractSyntaxTrees.AbstractSyntaxTree;
+import triangle.abstractSyntaxTrees.visitors.DeclarationVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public abstract class Declaration extends AbstractSyntaxTree {
+
+	public Declaration(SourcePosition position) {
+		super(position);
+		duplicated = false;
+	}
+
+	public boolean duplicated;
+
+	public abstract <TArg, TResult> TResult visit(DeclarationVisitor<TArg, TResult> visitor, TArg arg);
+
+	public <TArg, TResult> TResult visit(DeclarationVisitor<TArg, TResult> visitor) {
+		return visit(visitor, null);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/declarations/FuncDeclaration.java

@@ -0,0 +1,57 @@
+/*
+ * @(#)FuncDeclaration.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.declarations;
+
+import triangle.abstractSyntaxTrees.expressions.Expression;
+import triangle.abstractSyntaxTrees.formals.FormalParameterSequence;
+import triangle.abstractSyntaxTrees.terminals.Identifier;
+import triangle.abstractSyntaxTrees.types.TypeDenoter;
+import triangle.abstractSyntaxTrees.visitors.DeclarationVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class FuncDeclaration extends Declaration implements FunctionDeclaration {
+
+	public FuncDeclaration(Identifier iAST, FormalParameterSequence fpsAST, TypeDenoter tAST, Expression eAST,
+			SourcePosition position) {
+		super(position);
+		I = iAST;
+		FPS = fpsAST;
+		T = tAST;
+		E = eAST;
+	}
+
+	public <TArg, TResult> TResult visit(DeclarationVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitFuncDeclaration(this, arg);
+	}
+
+	@Override
+	public FormalParameterSequence getFormals() {
+		return FPS;
+	}
+	
+	@Override
+	public TypeDenoter getType() {
+		return T;
+	}
+	
+	public final Identifier I;
+	public final FormalParameterSequence FPS;
+	public TypeDenoter T;
+	public Expression E;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/declarations/FunctionDeclaration.java

@@ -0,0 +1,12 @@
+package triangle.abstractSyntaxTrees.declarations;
+
+import triangle.abstractSyntaxTrees.formals.FormalParameterSequence;
+import triangle.abstractSyntaxTrees.types.TypeDenoter;
+
+public interface FunctionDeclaration {
+
+	FormalParameterSequence getFormals();
+
+	TypeDenoter getType();
+	
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/declarations/ProcDeclaration.java

@@ -0,0 +1,48 @@
+/*
+ * @(#)ProcDeclaration.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.declarations;
+
+import triangle.abstractSyntaxTrees.commands.Command;
+import triangle.abstractSyntaxTrees.formals.FormalParameterSequence;
+import triangle.abstractSyntaxTrees.terminals.Identifier;
+import triangle.abstractSyntaxTrees.visitors.DeclarationVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class ProcDeclaration extends Declaration implements ProcedureDeclaration {
+
+	public ProcDeclaration(Identifier iAST, FormalParameterSequence fpsAST, Command cAST, SourcePosition position) {
+		super(position);
+		I = iAST;
+		FPS = fpsAST;
+		C = cAST;
+	}
+
+	public <TArg, TResult> TResult visit(DeclarationVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitProcDeclaration(this, arg);
+	}
+
+	@Override
+	public FormalParameterSequence getFormals() {
+		return FPS;
+	}
+
+	public final Identifier I;
+	public final FormalParameterSequence FPS;
+	public final Command C;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/declarations/ProcedureDeclaration.java

@@ -0,0 +1,9 @@
+package triangle.abstractSyntaxTrees.declarations;
+
+import triangle.abstractSyntaxTrees.formals.FormalParameterSequence;
+
+public interface ProcedureDeclaration {
+
+	FormalParameterSequence getFormals();
+	
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/declarations/SequentialDeclaration.java

@@ -0,0 +1,37 @@
+/*
+ * @(#)SequentialDeclaration.java               
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.declarations;
+
+import triangle.abstractSyntaxTrees.visitors.DeclarationVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class SequentialDeclaration extends Declaration {
+
+	public SequentialDeclaration(Declaration d1AST, Declaration d2AST, SourcePosition position) {
+		super(position);
+		D1 = d1AST;
+		D2 = d2AST;
+	}
+
+	public <TArg, TResult> TResult visit(DeclarationVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitSequentialDeclaration(this, arg);
+	}
+
+	public final Declaration D1, D2;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/declarations/UnaryOperatorDeclaration.java

@@ -0,0 +1,41 @@
+/*
+ * @(#)UnaryOperatorDeclaration.java               
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.declarations;
+
+import triangle.abstractSyntaxTrees.terminals.Operator;
+import triangle.abstractSyntaxTrees.types.TypeDenoter;
+import triangle.abstractSyntaxTrees.visitors.DeclarationVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class UnaryOperatorDeclaration extends Declaration {
+
+	public UnaryOperatorDeclaration(Operator oAST, TypeDenoter argAST, TypeDenoter resultAST, SourcePosition position) {
+		super(position);
+		O = oAST;
+		ARG = argAST;
+		RES = resultAST;
+	}
+
+	public <TArg, TResult> TResult visit(DeclarationVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitUnaryOperatorDeclaration(this, arg);
+	}
+
+	public final Operator O;
+	public final TypeDenoter ARG, RES;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/declarations/VarDeclaration.java

@@ -0,0 +1,45 @@
+/*
+ * @(#)VarDeclaration.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.declarations;
+
+import triangle.abstractSyntaxTrees.terminals.Identifier;
+import triangle.abstractSyntaxTrees.types.TypeDenoter;
+import triangle.abstractSyntaxTrees.visitors.DeclarationVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class VarDeclaration extends Declaration implements VariableDeclaration {
+
+	public VarDeclaration(Identifier iAST, TypeDenoter tAST, SourcePosition position) {
+		super(position);
+		I = iAST;
+		T = tAST;
+	}
+
+	@Override
+	public TypeDenoter getType() {
+		return T;
+	}
+	
+	public <TArg, TResult> TResult visit(DeclarationVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitVarDeclaration(this, arg);
+	}
+
+	public final Identifier I;
+	public TypeDenoter T;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/declarations/VariableDeclaration.java

@@ -0,0 +1,9 @@
+package triangle.abstractSyntaxTrees.declarations;
+
+import triangle.abstractSyntaxTrees.types.TypeDenoter;
+
+public interface VariableDeclaration {
+
+	TypeDenoter getType();
+	
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/expressions/ArrayExpression.java

@@ -0,0 +1,37 @@
+/*
+ * @(#)ArrayExpression.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.expressions;
+
+import triangle.abstractSyntaxTrees.aggregates.ArrayAggregate;
+import triangle.abstractSyntaxTrees.visitors.ExpressionVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class ArrayExpression extends Expression {
+
+	public ArrayExpression(ArrayAggregate aaAST, SourcePosition position) {
+		super(position);
+		AA = aaAST;
+	}
+
+	public <TArg, TResult> TResult visit(ExpressionVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitArrayExpression(this, arg);
+	}
+
+	public final ArrayAggregate AA;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/expressions/BinaryExpression.java

@@ -0,0 +1,41 @@
+/*
+ * @(#)BinaryExpression.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.expressions;
+
+import triangle.abstractSyntaxTrees.terminals.Operator;
+import triangle.abstractSyntaxTrees.visitors.ExpressionVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class BinaryExpression extends Expression {
+
+	public BinaryExpression(Expression e1AST, Operator oAST, Expression e2AST, SourcePosition position) {
+		super(position);
+		O = oAST;
+		E1 = e1AST;
+		E2 = e2AST;
+	}
+
+	public <TArg, TResult> TResult visit(ExpressionVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitBinaryExpression(this, arg);
+	}
+
+	public Expression E1;
+	public Expression E2;
+	public final Operator O;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/expressions/CallExpression.java

@@ -0,0 +1,40 @@
+/*
+ * @(#)CallExpression.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.expressions;
+
+import triangle.abstractSyntaxTrees.actuals.ActualParameterSequence;
+import triangle.abstractSyntaxTrees.terminals.Identifier;
+import triangle.abstractSyntaxTrees.visitors.ExpressionVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class CallExpression extends Expression {
+
+	public CallExpression(Identifier iAST, ActualParameterSequence apsAST, SourcePosition position) {
+		super(position);
+		I = iAST;
+		APS = apsAST;
+	}
+
+	public <TArg, TResult> TResult visit(ExpressionVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitCallExpression(this, arg);
+	}
+
+	public final Identifier I;
+	public final ActualParameterSequence APS;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/expressions/CharacterExpression.java

@@ -0,0 +1,47 @@
+/*
+ * @(#)CharacterExpression.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.expressions;
+
+import triangle.abstractSyntaxTrees.terminals.CharacterLiteral;
+import triangle.abstractSyntaxTrees.visitors.ExpressionVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class CharacterExpression extends Expression {
+
+	public CharacterExpression(CharacterLiteral clAST, SourcePosition position) {
+		super(position);
+		CL = clAST;
+	}
+
+	public <TArg, TResult> TResult visit(ExpressionVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitCharacterExpression(this, arg);
+	}
+
+	public final CharacterLiteral CL;
+	
+	@Override
+	public boolean isLiteral() {
+		return true;
+	}
+	
+	@Override
+	public int getValue() {
+		return CL.getValue();
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/expressions/EmptyExpression.java

@@ -0,0 +1,33 @@
+/*
+ * @(#)EmptyExpression.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.expressions;
+
+import triangle.abstractSyntaxTrees.visitors.ExpressionVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class EmptyExpression extends Expression {
+
+	public EmptyExpression(SourcePosition position) {
+		super(position);
+	}
+
+	public <TArg, TResult> TResult visit(ExpressionVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitEmptyExpression(this, arg);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/expressions/Expression.java

@@ -0,0 +1,48 @@
+/*
+ * @(#)Expression.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.expressions;
+
+import triangle.abstractSyntaxTrees.AbstractSyntaxTree;
+import triangle.abstractSyntaxTrees.types.TypeDenoter;
+import triangle.abstractSyntaxTrees.visitors.ExpressionVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public abstract class Expression extends AbstractSyntaxTree {
+
+	public Expression(SourcePosition position) {
+		super(position);
+		type = null;
+	}
+
+	public TypeDenoter type;
+
+	public boolean isLiteral() {
+		return false;
+	}
+
+	public int getValue() {
+		throw new UnsupportedOperationException();
+	}
+
+	public abstract <TArg, TResult> TResult visit(ExpressionVisitor<TArg, TResult> visitor, TArg arg);
+
+	public <TArg, TResult> TResult visit(ExpressionVisitor<TArg, TResult> visitor) {
+		return visit(visitor, null);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/expressions/IfExpression.java

@@ -0,0 +1,40 @@
+/*
+ * @(#)IfExpression.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.expressions;
+
+import triangle.abstractSyntaxTrees.visitors.ExpressionVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class IfExpression extends Expression {
+
+	public IfExpression(Expression e1AST, Expression e2AST, Expression e3AST, SourcePosition position) {
+		super(position);
+		E1 = e1AST;
+		E2 = e2AST;
+		E3 = e3AST;
+	}
+
+	public <TArg, TResult> TResult visit(ExpressionVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitIfExpression(this, arg);
+	}
+
+	public Expression E1;
+	public Expression E2;
+	public Expression E3;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/expressions/IntegerExpression.java

@@ -0,0 +1,47 @@
+/*
+ * @(#)IntegerExpression.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.expressions;
+
+import triangle.abstractSyntaxTrees.terminals.IntegerLiteral;
+import triangle.abstractSyntaxTrees.visitors.ExpressionVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class IntegerExpression extends Expression {
+
+	public IntegerExpression(IntegerLiteral ilAST, SourcePosition position) {
+		super(position);
+		IL = ilAST;
+	}
+
+	public <TArg, TResult> TResult visit(ExpressionVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitIntegerExpression(this, arg);
+	}
+
+	public final IntegerLiteral IL;
+
+	@Override
+	public boolean isLiteral() {
+		return true;
+	}
+
+	@Override
+	public int getValue() {
+		return IL.getValue();
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/expressions/LetExpression.java

@@ -0,0 +1,39 @@
+/*
+ * @(#)LetExpression.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.expressions;
+
+import triangle.abstractSyntaxTrees.declarations.Declaration;
+import triangle.abstractSyntaxTrees.visitors.ExpressionVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class LetExpression extends Expression {
+
+	public LetExpression(Declaration dAST, Expression eAST, SourcePosition position) {
+		super(position);
+		D = dAST;
+		E = eAST;
+	}
+
+	public <TArg, TResult> TResult visit(ExpressionVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitLetExpression(this, arg);
+	}
+
+	public final Declaration D;
+	public Expression E;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/expressions/RecordExpression.java

@@ -0,0 +1,37 @@
+/*
+ * @(#)RecordExpression.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.expressions;
+
+import triangle.abstractSyntaxTrees.aggregates.RecordAggregate;
+import triangle.abstractSyntaxTrees.visitors.ExpressionVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class RecordExpression extends Expression {
+
+	public RecordExpression(RecordAggregate raAST, SourcePosition position) {
+		super(position);
+		RA = raAST;
+	}
+
+	public <TArg, TResult> TResult visit(ExpressionVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitRecordExpression(this, arg);
+	}
+
+	public final RecordAggregate RA;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/expressions/UnaryExpression.java

@@ -0,0 +1,39 @@
+/*
+ * @(#)UnaryExpression.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.expressions;
+
+import triangle.abstractSyntaxTrees.terminals.Operator;
+import triangle.abstractSyntaxTrees.visitors.ExpressionVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class UnaryExpression extends Expression {
+
+	public UnaryExpression(Operator oAST, Expression eAST, SourcePosition position) {
+		super(position);
+		O = oAST;
+		E = eAST;
+	}
+
+	public <TArg, TResult> TResult visit(ExpressionVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitUnaryExpression(this, arg);
+	}
+
+	public Expression E;
+	public final Operator O;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/expressions/VnameExpression.java

@@ -0,0 +1,37 @@
+/*
+ * @(#)VnameExpression.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.expressions;
+
+import triangle.abstractSyntaxTrees.visitors.ExpressionVisitor;
+import triangle.abstractSyntaxTrees.vnames.Vname;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class VnameExpression extends Expression {
+
+	public VnameExpression(Vname vAST, SourcePosition position) {
+		super(position);
+		V = vAST;
+	}
+
+	public <TArg, TResult> TResult visit(ExpressionVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitVnameExpression(this, arg);
+	}
+
+	public final Vname V;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/formals/ConstFormalParameter.java

@@ -0,0 +1,55 @@
+/*
+ * @(#)ConstFormalParameter.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.formals;
+
+import triangle.abstractSyntaxTrees.declarations.ConstantDeclaration;
+import triangle.abstractSyntaxTrees.terminals.Identifier;
+import triangle.abstractSyntaxTrees.types.TypeDenoter;
+import triangle.abstractSyntaxTrees.visitors.DeclarationVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class ConstFormalParameter extends FormalParameter implements ConstantDeclaration {
+
+	public ConstFormalParameter(Identifier iAST, TypeDenoter tAST, SourcePosition position) {
+		super(position);
+		I = iAST;
+		T = tAST;
+	}
+
+	@Override
+	public TypeDenoter getType() {
+		return T;
+	}
+
+	public <TArg, TResult> TResult visit(DeclarationVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitConstFormalParameter(this, arg);
+	}
+
+	@Override
+	public boolean equals(Object fpAST) {
+		if (fpAST instanceof ConstFormalParameter) {
+			return T.equals(((ConstFormalParameter)fpAST).T);
+		} else {
+			return false;
+		}
+	}
+
+	public final Identifier I;
+	public TypeDenoter T;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/formals/EmptyFormalParameterSequence.java

@@ -0,0 +1,38 @@
+/*
+ * @(#)EmptyFormalParameterSequence.java       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.formals;
+
+import triangle.abstractSyntaxTrees.visitors.FormalParameterSequenceVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class EmptyFormalParameterSequence extends FormalParameterSequence {
+
+	public EmptyFormalParameterSequence(SourcePosition position) {
+		super(position);
+	}
+
+	public <TArg, TResult> TResult visit(FormalParameterSequenceVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitEmptyFormalParameterSequence(this, arg);
+	}
+
+	@Override
+	public boolean equals(Object fpsAST) {
+		return (fpsAST instanceof EmptyFormalParameterSequence);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/formals/FormalParameter.java

@@ -0,0 +1,39 @@
+/*
+ * @(#)FormalParameter.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.formals;
+
+import triangle.abstractSyntaxTrees.declarations.Declaration;
+import triangle.abstractSyntaxTrees.visitors.DeclarationVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public abstract class FormalParameter extends Declaration {
+
+	public FormalParameter(SourcePosition position) {
+		super(position);
+	}
+
+	@Override
+	public abstract boolean equals(Object fpAST);
+
+	public abstract <TArg, TResult> TResult visit(DeclarationVisitor<TArg, TResult> visitor, TArg arg);
+
+	public <TArg, TResult> TResult visit(DeclarationVisitor<TArg, TResult> visitor) {
+		return visit(visitor, null);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/formals/FormalParameterSequence.java

@@ -0,0 +1,39 @@
+/*
+ * @(#)FormalParameterSequence.java               
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.formals;
+
+import triangle.abstractSyntaxTrees.AbstractSyntaxTree;
+import triangle.abstractSyntaxTrees.visitors.FormalParameterSequenceVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public abstract class FormalParameterSequence extends AbstractSyntaxTree {
+
+	public FormalParameterSequence(SourcePosition position) {
+		super(position);
+	}
+
+	@Override
+	public abstract boolean equals(Object fpsAST);
+
+	public abstract <TArg, TResult> TResult visit(FormalParameterSequenceVisitor<TArg, TResult> visitor, TArg arg);
+
+	public <TArg, TResult> TResult visit(FormalParameterSequenceVisitor<TArg, TResult> visitor) {
+		return visit(visitor, null);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/formals/FuncFormalParameter.java

@@ -0,0 +1,63 @@
+/*
+ * @(#)FuncFormalParameter.java               
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.formals;
+
+import triangle.abstractSyntaxTrees.declarations.FunctionDeclaration;
+import triangle.abstractSyntaxTrees.terminals.Identifier;
+import triangle.abstractSyntaxTrees.types.TypeDenoter;
+import triangle.abstractSyntaxTrees.visitors.DeclarationVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class FuncFormalParameter extends FormalParameter implements FunctionDeclaration {
+
+	public FuncFormalParameter(Identifier iAST, FormalParameterSequence fpsAST, TypeDenoter tAST,
+			SourcePosition position) {
+		super(position);
+		I = iAST;
+		FPS = fpsAST;
+		T = tAST;
+	}
+
+	public <TArg, TResult> TResult visit(DeclarationVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitFuncFormalParameter(this, arg);
+	}
+
+	@Override
+	public FormalParameterSequence getFormals() {
+		return FPS;
+	}
+	
+	@Override
+	public TypeDenoter getType() {
+		return T;
+	}
+	
+	@Override
+	public boolean equals(Object fpAST) {
+		if (fpAST instanceof FuncFormalParameter) {
+			FuncFormalParameter ffpAST = (FuncFormalParameter) fpAST;
+			return FPS.equals(ffpAST.FPS) && T.equals(ffpAST.T);
+		} else
+			return false;
+	}
+
+	public final Identifier I;
+	public final FormalParameterSequence FPS;
+	public TypeDenoter T;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/formals/MultipleFormalParameterSequence.java

@@ -0,0 +1,49 @@
+/*
+ * @(#)MultipleFormalParameterSequence.java       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.formals;
+
+import triangle.abstractSyntaxTrees.visitors.FormalParameterSequenceVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class MultipleFormalParameterSequence extends FormalParameterSequence {
+
+	public MultipleFormalParameterSequence(FormalParameter fpAST, FormalParameterSequence fpsAST,
+			SourcePosition position) {
+		super(position);
+		FP = fpAST;
+		FPS = fpsAST;
+	}
+
+	public <TArg, TResult> TResult visit(FormalParameterSequenceVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitMultipleFormalParameterSequence(this, arg);
+	}
+
+	@Override
+	public boolean equals(Object fpsAST) {
+		if (fpsAST instanceof MultipleFormalParameterSequence) {
+			MultipleFormalParameterSequence mfpsAST = (MultipleFormalParameterSequence) fpsAST;
+			return FP.equals(mfpsAST.FP) && FPS.equals(mfpsAST.FPS);
+		} else {
+			return false;
+		}
+	}
+
+	public final FormalParameter FP;
+	public final FormalParameterSequence FPS;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/formals/ProcFormalParameter.java

@@ -0,0 +1,55 @@
+/*
+ * @(#)ProcFormalParameter.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.formals;
+
+import triangle.abstractSyntaxTrees.declarations.ProcedureDeclaration;
+import triangle.abstractSyntaxTrees.terminals.Identifier;
+import triangle.abstractSyntaxTrees.visitors.DeclarationVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class ProcFormalParameter extends FormalParameter implements ProcedureDeclaration {
+
+	public ProcFormalParameter(Identifier iAST, FormalParameterSequence fpsAST, SourcePosition position) {
+		super(position);
+		I = iAST;
+		FPS = fpsAST;
+	}
+
+	public <TArg, TResult> TResult visit(DeclarationVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitProcFormalParameter(this, arg);
+	}
+
+	@Override
+	public FormalParameterSequence getFormals() {
+		return FPS;
+	}
+
+	@Override
+	public boolean equals(Object fpAST) {
+		if (fpAST instanceof ProcFormalParameter) {
+			ProcFormalParameter pfpAST = (ProcFormalParameter) fpAST;
+			return FPS.equals(pfpAST.FPS);
+		} else {
+			return false;
+		}
+	}
+
+	public final Identifier I;
+	public final FormalParameterSequence FPS;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/formals/SingleFormalParameterSequence.java

@@ -0,0 +1,46 @@
+/*
+ * @(#)SingleFormalParameterSequence.java               
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.formals;
+
+import triangle.abstractSyntaxTrees.visitors.FormalParameterSequenceVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class SingleFormalParameterSequence extends FormalParameterSequence {
+
+	public SingleFormalParameterSequence(FormalParameter fpAST, SourcePosition position) {
+		super(position);
+		FP = fpAST;
+	}
+
+	public <TArg, TResult> TResult visit(FormalParameterSequenceVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitSingleFormalParameterSequence(this, arg);
+	}
+
+	@Override
+	public boolean equals(Object fpsAST) {
+		if (fpsAST instanceof SingleFormalParameterSequence) {
+			SingleFormalParameterSequence sfpsAST = (SingleFormalParameterSequence) fpsAST;
+			return FP.equals(sfpsAST.FP);
+		} else {
+			return false;
+		}
+	}
+
+	public final FormalParameter FP;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/formals/VarFormalParameter.java

@@ -0,0 +1,55 @@
+/*
+ * @(#)ValFormalParameter.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.formals;
+
+import triangle.abstractSyntaxTrees.declarations.VariableDeclaration;
+import triangle.abstractSyntaxTrees.terminals.Identifier;
+import triangle.abstractSyntaxTrees.types.TypeDenoter;
+import triangle.abstractSyntaxTrees.visitors.DeclarationVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class VarFormalParameter extends FormalParameter implements VariableDeclaration {
+
+	public VarFormalParameter(Identifier iAST, TypeDenoter tAST, SourcePosition position) {
+		super(position);
+		I = iAST;
+		T = tAST;
+	}
+
+	@Override
+	public TypeDenoter getType() {
+		return T;
+	}
+
+	public <TArg, TResult> TResult visit(DeclarationVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitVarFormalParameter(this, arg);
+	}
+
+	@Override
+	public boolean equals(Object fpAST) {
+		if (fpAST instanceof VarFormalParameter) {
+			return T.equals(((VarFormalParameter)fpAST).T);
+		} else {
+			return false;
+		}
+	}
+
+	public final Identifier I;
+	public TypeDenoter T;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/terminals/CharacterLiteral.java

@@ -0,0 +1,41 @@
+/*
+ * @(#)CharacterLiteral.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.terminals;
+
+import triangle.abstractSyntaxTrees.visitors.LiteralVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class CharacterLiteral extends Terminal {
+
+	public CharacterLiteral(String spelling, SourcePosition position) {
+		super(spelling, position);
+	}
+
+	public <TArg, TResult> TResult visit(LiteralVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitCharacterLiteral(this, arg);
+	}
+
+	public <TArg, TResult> TResult visit(LiteralVisitor<TArg, TResult> visitor) {
+		return visit(visitor, null);
+	}
+
+	public int getValue() {
+		return spelling.charAt(1);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/terminals/Identifier.java

@@ -0,0 +1,44 @@
+/*
+ * @(#)Identifier.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.terminals;
+
+import triangle.abstractSyntaxTrees.AbstractSyntaxTree;
+import triangle.abstractSyntaxTrees.types.TypeDenoter;
+import triangle.abstractSyntaxTrees.visitors.IdentifierVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class Identifier extends Terminal {
+
+	public Identifier(String spelling, SourcePosition position) {
+		super(spelling, position);
+		type = null;
+		decl = null;
+	}
+
+	public TypeDenoter type;
+	public AbstractSyntaxTree decl; // Either a Declaration or a FieldTypeDenoter
+
+	public <TArg, TResult> TResult visit(IdentifierVisitor<TArg, TResult> visitor, TArg arg) {
+		return visitor.visitIdentifier(this, arg);
+	}
+
+	public <TArg, TResult> TResult visit(IdentifierVisitor<TArg, TResult> visitor) {
+		return visit(visitor, null);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/terminals/IntegerLiteral.java

@@ -0,0 +1,41 @@
+/*
+ * @(#)IntegerLiteral.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.terminals;
+
+import triangle.abstractSyntaxTrees.visitors.LiteralVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class IntegerLiteral extends Terminal {
+
+	public IntegerLiteral(String spelling, SourcePosition position) {
+		super(spelling, position);
+	}
+
+	public <TArg, TResult> TResult visit(LiteralVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitIntegerLiteral(this, arg);
+	}
+
+	public <TArg, TResult> TResult visit(LiteralVisitor<TArg, TResult> visitor) {
+		return visit(visitor, null);
+	}
+
+	public int getValue() {
+		return Integer.parseInt(spelling);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/terminals/Operator.java

@@ -0,0 +1,41 @@
+/*
+ * @(#)Operator.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.terminals;
+
+import triangle.abstractSyntaxTrees.declarations.Declaration;
+import triangle.abstractSyntaxTrees.visitors.OperatorVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class Operator extends Terminal {
+
+	public Operator(String spelling, SourcePosition position) {
+		super(spelling, position);
+		decl = null;
+	}
+
+	public Declaration decl;
+
+	public <TArg, TResult> TResult visit(OperatorVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitOperator(this, arg);
+	}
+
+	public <TArg, TResult> TResult visit(OperatorVisitor<TArg, TResult> visitor) {
+		return visit(visitor, null);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/terminals/Terminal.java

@@ -0,0 +1,32 @@
+/*
+ * @(#)Terminal.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.terminals;
+
+import triangle.abstractSyntaxTrees.AbstractSyntaxTree;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public abstract class Terminal extends AbstractSyntaxTree {
+
+	public Terminal(String spelling, SourcePosition position) {
+		super(position);
+		this.spelling = spelling;
+	}
+
+	public final String spelling;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/types/AnyTypeDenoter.java

@@ -0,0 +1,43 @@
+/*
+ * @(#)AnyTypeDenoter.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.types;
+
+import triangle.abstractSyntaxTrees.visitors.TypeDenoterVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class AnyTypeDenoter extends TypeDenoter {
+
+	public AnyTypeDenoter(SourcePosition position) {
+		super(position);
+	}
+
+	public <TArg, TResult> TResult visit(TypeDenoterVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitAnyTypeDenoter(this, arg);
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		return false;
+	}
+	
+	@Override
+	public int getSize() {
+		return 0;
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/types/ArrayTypeDenoter.java

@@ -0,0 +1,56 @@
+/*
+ * @(#)ArrayTypeDenoter.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.types;
+
+import triangle.abstractSyntaxTrees.terminals.IntegerLiteral;
+import triangle.abstractSyntaxTrees.visitors.TypeDenoterVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class ArrayTypeDenoter extends TypeDenoter {
+
+	public ArrayTypeDenoter(IntegerLiteral ilAST, TypeDenoter tAST, SourcePosition position) {
+		super(position);
+		IL = ilAST;
+		T = tAST;
+	}
+
+	public <TArg, TResult> TResult visit(TypeDenoterVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitArrayTypeDenoter(this, arg);
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if (obj != null && obj instanceof ErrorTypeDenoter) {
+			return true;
+		} else if (obj != null && obj instanceof ArrayTypeDenoter) {
+			return this.IL.spelling.compareTo(((ArrayTypeDenoter) obj).IL.spelling) == 0
+					&& this.T.equals(((ArrayTypeDenoter) obj).T);
+		} else {
+			return false;
+		}
+	}
+	
+	@Override
+	public int getSize() {
+		return IL.getValue() * T.getSize();
+	}
+
+	public final IntegerLiteral IL;
+	public TypeDenoter T;
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/types/BoolTypeDenoter.java

@@ -0,0 +1,48 @@
+/*
+ * @(#)BoolTypeDenoter.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.types;
+
+import triangle.abstractMachine.Machine;
+import triangle.abstractSyntaxTrees.visitors.TypeDenoterVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class BoolTypeDenoter extends TypeDenoter {
+
+	public BoolTypeDenoter(SourcePosition position) {
+		super(position);
+	}
+
+	public <TArg, TResult> TResult visit(TypeDenoterVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitBoolTypeDenoter(this, arg);
+	}
+	
+	@Override
+	public int getSize() {
+		return Machine.booleanSize;
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if ((obj != null) && (obj instanceof ErrorTypeDenoter)) {
+			return true;
+		} else {
+			return ((obj != null) && (obj instanceof BoolTypeDenoter));
+		}
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/types/CharTypeDenoter.java

@@ -0,0 +1,48 @@
+/*
+ * @(#)CharTypeDenoter.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.types;
+
+import triangle.abstractMachine.Machine;
+import triangle.abstractSyntaxTrees.visitors.TypeDenoterVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class CharTypeDenoter extends TypeDenoter {
+
+	public CharTypeDenoter(SourcePosition position) {
+		super(position);
+	}
+
+	public <TArg, TResult> TResult visit(TypeDenoterVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitCharTypeDenoter(this, arg);
+	}
+	
+	@Override
+	public int getSize() {
+		return Machine.characterSize;
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if (obj != null && obj instanceof ErrorTypeDenoter) {
+			return true;
+		} else {
+			return (obj != null && obj instanceof CharTypeDenoter);
+		}
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/types/ErrorTypeDenoter.java

@@ -0,0 +1,43 @@
+/*
+ * @(#)ErrorTypeDenoter.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.types;
+
+import triangle.abstractSyntaxTrees.visitors.TypeDenoterVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class ErrorTypeDenoter extends TypeDenoter {
+
+	public ErrorTypeDenoter(SourcePosition position) {
+		super(position);
+	}
+
+	public <TArg, TResult> TResult visit(TypeDenoterVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitErrorTypeDenoter(this, arg);
+	}
+
+	@Override
+	public int getSize() {
+		return 0;
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		return true;
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/types/FieldTypeDenoter.java

@@ -0,0 +1,28 @@
+/*
+ * @(#)FieldTypeDenoter.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.types;
+
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public abstract class FieldTypeDenoter extends TypeDenoter {
+
+	public FieldTypeDenoter(SourcePosition position) {
+		super(position);
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/types/IntTypeDenoter.java

@@ -0,0 +1,48 @@
+/*
+ * @(#)IntTypeDenoter.java                       
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.types;
+
+import triangle.abstractMachine.Machine;
+import triangle.abstractSyntaxTrees.visitors.TypeDenoterVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class IntTypeDenoter extends TypeDenoter {
+
+	public IntTypeDenoter(SourcePosition position) {
+		super(position);
+	}
+
+	public <TArg, TResult> TResult visit(TypeDenoterVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitIntTypeDenoter(this, arg);
+	}
+	
+	@Override
+	public int getSize() {
+		return Machine.integerSize;
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if (obj != null && obj instanceof ErrorTypeDenoter) {
+			return true;
+		} else {
+			return (obj != null && obj instanceof IntTypeDenoter);
+		}
+	}
+}

Triangle.Compiler/src/main/java/triangle/abstractSyntaxTrees/types/MultipleFieldTypeDenoter.java

@@ -0,0 +1,57 @@
+/*
+ * @(#)MultipleFieldTypeDenoter.java               
+ * 
+ * Revisions and updates (c) 2022-2023 Sandy Brownlee. alexander.brownlee@stir.ac.uk
+ * 
+ * Original release:
+ *
+ * Copyright (C) 1999, 2003 D.A. Watt and D.F. Brown
+ * Dept. of Computing Science, University of Glasgow, Glasgow G12 8QQ Scotland
+ * and School of Computer and Math Sciences, The Robert Gordon University,
+ * St. Andrew Street, Aberdeen AB25 1HG, Scotland.
+ * All rights reserved.
+ *
+ * This software is provided free for educational use only. It may
+ * not be used for commercial purposes without the prior written permission
+ * of the authors.
+ */
+
+package triangle.abstractSyntaxTrees.types;
+
+import triangle.abstractSyntaxTrees.terminals.Identifier;
+import triangle.abstractSyntaxTrees.visitors.TypeDenoterVisitor;
+import triangle.syntacticAnalyzer.SourcePosition;
+
+public class MultipleFieldTypeDenoter extends FieldTypeDenoter {
+
+	public MultipleFieldTypeDenoter(Identifier iAST, TypeDenoter tAST, FieldTypeDenoter ftAST,
+			SourcePosition position) {
+		super(position);
+		I = iAST;
+		T = tAST;
+		FT = ftAST;
+	}
+
+	public <TArg, TResult> TResult visit(TypeDenoterVisitor<TArg, TResult> v, TArg arg) {
+		return v.visitMultipleFieldTypeDenoter(this, arg);
+	}
+	
+	@Override
+	public int getSize() {
+		return T.getSize() + FT.getSize();
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if (obj != null && obj instanceof MultipleFieldTypeDenoter) {
+			MultipleFieldTypeDenoter ft = (MultipleFieldTypeDenoter) obj;
+			return (this.I.spelling.compareTo(ft.I.spelling) == 0) && this.T.equals(ft.T) && this.FT.equals(ft.FT);
+		} else {
+			return false;
+		}
+	}
+
+	public final Identifier I;
+	public TypeDenoter T;
+	public FieldTypeDenoter FT;
+}