loopwhilecom. now works

.classpath

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-11/"/>
+	<classpathentry kind="con" path="org.eclipse.buildship.core.gradleclasspathcontainer"/>
+	<classpathentry kind="output" path="bin/default"/>
+</classpath>

.gitignore

@@ -60,3 +60,4 @@ local.properties
 # Typically, this file would be tracked if it contains build/dependency configurations:
 #.project
 /.gradle/
+/build/

.project

@@ -1,10 +1,15 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <projectDescription>
-	<name>a5-triangle-tools</name>
+	<name>Triangle-Tools</name>
 	<comment>Project a5-triangle-tools created by Buildship.</comment>
 	<projects>
 	</projects>
 	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
 		<buildCommand>
 			<name>org.eclipse.buildship.core.gradleprojectbuilder</name>
 			<arguments>
@@ -12,6 +17,7 @@
 		</buildCommand>
 	</buildSpec>
 	<natures>
+		<nature>org.eclipse.jdt.core.javanature</nature>
 		<nature>org.eclipse.buildship.core.gradleprojectnature</nature>
 	</natures>
 </projectDescription>

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

@@ -181,11 +181,29 @@ public final class Encoder implements ActualParameterVisitor<Frame, Integer>,
 		var loopAddr = emitter.getNextInstrAddr();
 		ast.C.visit(this, frame);
 		emitter.patch(jumpAddr);
+		
 		ast.E.visit(this, frame);
 		emitter.emit(OpCode.JUMPIF, Machine.trueRep, Register.CB, loopAddr);
 		return null;
 	}
 	
+	@Override
+	public Void visitLoopWhile(LoopWhile ast, Frame frame) {
+		var loopAddr = emitter.getNextInstrAddr();
+		ast.C1.visit(this, frame); //(LOOP = C1)
+		
+		ast.E.visit(this, frame); //check if the while is false first (WHILE = E)
+		var jumpIfAddr = emitter.emit(OpCode.JUMPIF, Machine.falseRep, Register.CB, 0);
+								  //store this address
+		
+		ast.C2.visit(this, frame); // visit the do section now (DO = C2)
+		emitter.emit(OpCode.JUMP, Machine.trueRep, Register.CB, loopAddr); //jump back to C1
+		
+		emitter.patch(jumpIfAddr); //patch the jmpIfAddr to go back to the while section
+	
+		return null;
+	}
+
 	// Expressions
 	@Override
 	public Integer visitArrayExpression(ArrayExpression ast, Frame frame) {
@@ -794,10 +812,4 @@ public final class Encoder implements ActualParameterVisitor<Frame, Integer>,
 		var baseObject = (AddressableEntity) V.visit(this, frame);
 		baseObject.encodeFetchAddress(emitter, frame, V);
 	}
-
-	@Override
-	public Void visitLoopWhile(LoopWhile loopWhile, Frame arg) {
-		// TODO Auto-generated method stub
-		return null;
-	}
 }

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

@@ -497,6 +497,17 @@ public class ConstantFolder implements ActualParameterVisitor<Void, AbstractSynt
 		return null;
 	}
 	
+	@Override
+	public AbstractSyntaxTree visitLoopWhile(LoopWhile ast, Void arg) {
+		ast.C1.visit(this);
+		AbstractSyntaxTree replacement = ast.E.visit(this);
+		if (replacement != null) {
+			ast.E = (Expression) replacement;
+		}
+		ast.C2.visit(this);
+		return null;
+	}
+
 	// TODO uncomment if you've implemented the repeat command
 //	@Override
 //	public AbstractSyntaxTree visitRepeatCommand(RepeatCommand ast, Void arg) {
@@ -596,11 +607,4 @@ public class ConstantFolder implements ActualParameterVisitor<Void, AbstractSynt
 		// any unhandled situation (i.e., not foldable) is ignored
 		return null;
 	}
-
-	@Override
-	public AbstractSyntaxTree visitLoopWhile(LoopWhile loopWhile, Void arg) {
-		// TODO Auto-generated method stub
-		return null;
-	}
-
 }

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

@@ -386,7 +386,6 @@ public class Parser {
 		case Token.IN:
 		case Token.EOT:
 		case Token.RCURLY:
-
 			finish(commandPos);
 			commandAST = new EmptyCommand(commandPos);
 			break;

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

@@ -169,7 +169,7 @@ public class LayoutVisitor implements ActualParameterVisitor<Void, DrawingTree>,
 		var d1 = ast.C1.visit(this);
 		var d2 = ast.E.visit(this);
 		var d3 = ast.C2.visit(this);
-		return layoutTernary("LoopWhile.", d1, d2, d3);
+		return layoutTernary("LoopWhileCom.", d1, d2, d3);
 	}
 	
 	

Triangle.Compiler/src/test/java/triangle/syntacticAnalyser/TestScanner.java

@@ -53,6 +53,11 @@ public class TestScanner {
 		compileExpectSuccess("/while-curly.tri");
 	}
 	
+	@Test
+	public void testLoopWhileDoCommand() {
+		compileExpectSuccess("/loopwhile.tri");
+	}
+	
 	private void compileExpectSuccess(String filename) {
 		// build.gradle has a line sourceSets.test.resources.srcDir file("$rootDir/programs")
 		// which adds the programs directory to the list of places Java can easily find files

programs/loopwhile.tri

@@ -6,9 +6,6 @@ let
 in
 begin
   a := 0;
-  b := 10;
-  putint(b);
-
   loop
   begin
     put('a');
@@ -16,5 +13,4 @@ begin
   end
   while a < 5 do
   	put('b');
-  
 end