Comments containing information on is done/needs to be done

2 files changed, 330 insertions, 271 deletions

diff --git a/minijava/SymTableVis.java b/minijava/SymTableVis.java
index e0854f0..65e511f 100644
--- a/minijava/SymTableVis.java
+++ b/minijava/SymTableVis.java
@@ -29,6 +29,8 @@ public class SymTableVis<R,A> extends GJDepthFirst<R,A> {
 
         TypeEnum type = TypeEnum.ERROR;
         switch (n.f0.f0.which) {
+        case 0:
+            type = TypeEnum.int_array; break;
         case 2:
             type = TypeEnum.integer; break;
         default:
diff --git a/minijava/TypeCheckSimp.java b/minijava/TypeCheckSimp.java
index ab5d8c9..f9e71bd 100644
--- a/minijava/TypeCheckSimp.java
+++ b/minijava/TypeCheckSimp.java
@@ -13,29 +13,29 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
     private int offset;
 
     private void printNode(Node n, HashMap<String,TypeEnum> argu, boolean enter, TypeEnum consensus) {
-	for (int i=0; i < this.offset; ++i)
+        for (int i=0; i < this.offset; ++i)
             System.out.print(".");
-	if (enter)
+        if (enter)
             System.out.print("Visiting ");
         else
             System.out.print("Leaving ");
         System.out.print(n.getClass().getSimpleName());
-	if (!enter) {
-	    if (consensus == TypeEnum.ERROR)
-		System.out.print(" did not type check.");
-	    else
-		System.out.print(" found type " + consensus);
-	}
-	System.out.println();
+        if (!enter) {
+            if (consensus == TypeEnum.ERROR)
+                System.out.print(" did not type check.");
+            else
+                System.out.print(" found type " + consensus);
+        }
+        System.out.println();
     }
 
     //
     // Auto class visitors--probably don't need to be overridden.
     //
     public TypeInstance visit(NodeList n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance ret = new TypeInstance(TypeEnum.CHECK);
         int _count=0;
         for ( Enumeration<Node> e = n.elements(); e.hasMoreElements(); ) {
@@ -45,17 +45,17 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
                 ret = node;
             _count++;
         }
-	
-	this.printNode(n, argu, false, ret.get_type()); 
-	--this.offset;
+
+        this.printNode(n, argu, false, ret.get_type());
+        --this.offset;
         return ret;
     }
 
     public TypeInstance visit(NodeListOptional n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
-	TypeInstance ret;
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
+        TypeInstance ret;
         if ( n.present() ) { // FIXME "present" seems to check if any nodes exist at all!
             ret = new TypeInstance(TypeEnum.CHECK);
             int _count=0;
@@ -68,33 +68,33 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
         }
         else
             ret = new TypeInstance(TypeEnum.CHECK); // FIXME used to read 'null'
-	
-	this.printNode(n, argu, false, ret.get_type()); 
-	--this.offset;
-	return ret;
+
+        this.printNode(n, argu, false, ret.get_type());
+        --this.offset;
+        return ret;
     }
 
     // FIXME
     public TypeInstance visit(NodeOptional n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
+        TypeInstance ret;
 
-	TypeInstance ret;
-	
         if ( n.present() )
             ret = n.node.accept(this,argu);
         else
             ret = new TypeInstance(TypeEnum.CHECK);
-	
-	this.printNode(n, argu, false, ret.get_type()); 
-	--this.offset;
-	return ret;
+
+        this.printNode(n, argu, false, ret.get_type());
+        --this.offset;
+        return ret;
     }
 
     public TypeInstance visit(NodeSequence n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance ret = new TypeInstance(TypeEnum.CHECK);
         int _count=0;
         for ( Enumeration<Node> e = n.elements(); e.hasMoreElements(); ) {
@@ -104,16 +104,16 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
             _count++;
         }
 
-	this.printNode(n, argu, false, ret.get_type()); 
-	--this.offset;
+        this.printNode(n, argu, false, ret.get_type());
+        --this.offset;
         return ret;
     }
 
     public TypeInstance visit(NodeToken n, HashMap<String,TypeEnum> argu) {
-	// A fixed string token. '⌣'
-	++this.offset;
-	// this.printNode(n, argu, false, null); 
-	--this.offset;
+        // A fixed string token. '⌣'
+        ++this.offset;
+        // this.printNode(n, argu, false, null);
+        --this.offset;
         return null;
     }
 
@@ -127,15 +127,15 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f2 -> <EOF>
      */
     public TypeInstance visit(Goal n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance ret = n.f0.accept(this, argu);
         n.f1.accept(this, argu);
         n.f2.accept(this, argu);
-	
-	this.printNode(n, argu, false, ret.get_type()); 
-	--this.offset;
+
+        this.printNode(n, argu, false, ret.get_type());
+        --this.offset;
         return ret;
     }
 
@@ -160,9 +160,9 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f17 -> "}"
      */
     public TypeInstance visit(MainClass n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         n.f0.accept(this, argu);
         TypeInstance name = n.f1.accept(this, argu);
         n.f2.accept(this, argu);
@@ -182,8 +182,8 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
         n.f16.accept(this, argu);
         n.f17.accept(this, argu);
 
-	this.printNode(n, argu, false, stmt.get_type());
-	--this.offset;
+        this.printNode(n, argu, false, stmt.get_type());
+        --this.offset;
         return stmt;
     }
 
@@ -192,13 +192,13 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      *               | ClassExtendsDeclaration()
      */
     public TypeInstance visit(TypeDeclaration n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance ret = n.f0.accept(this, argu);
-	
-	this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+
+        this.printNode(n, argu, false, ret.get_type());
+        --this.offset;
         return ret;
     }
 
@@ -211,9 +211,9 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f5 -> "}"
      */
     public TypeInstance visit(ClassDeclaration n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance _ret=null;
         n.f0.accept(this, argu);
         n.f1.accept(this, argu);
@@ -221,7 +221,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
         n.f3.accept(this, argu);
         n.f4.accept(this, argu);
         n.f5.accept(this, argu);
-	--this.offset;
+        --this.offset;
         return _ret;
     }
 
@@ -236,9 +236,9 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f7 -> "}"
      */
     public TypeInstance visit(ClassExtendsDeclaration n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance _ret=null;
         n.f0.accept(this, argu);
         n.f1.accept(this, argu);
@@ -248,7 +248,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
         n.f5.accept(this, argu);
         n.f6.accept(this, argu);
         n.f7.accept(this, argu);
-	--this.offset;
+        --this.offset;
         return _ret;
     }
 
@@ -259,15 +259,15 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f2 -> ";"
      */
     public TypeInstance visit(VarDeclaration n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance ret = n.f0.accept(this, argu);
         n.f1.accept(this, argu);
         n.f2.accept(this, argu);
-	
-	this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+
+        this.printNode(n, argu, false, ret.get_type());
+        --this.offset;
         return ret;
     }
 
@@ -288,9 +288,9 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f12 -> "}"
      */
     public TypeInstance visit(MethodDeclaration n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         n.f0.accept(this, argu);
         TypeInstance ret_type = n.f1.accept(this, argu);
         n.f2.accept(this, argu);
@@ -304,13 +304,13 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
         TypeInstance retur = n.f10.accept(this, argu);
         n.f11.accept(this, argu);
         n.f12.accept(this, argu);
-	TypeInstance ret = (stmt.equal_type(ret_type) &&
-			    stmt.get_type() == TypeEnum.CHECK) ?
-	    new TypeInstance(TypeEnum.CHECK) :
-	    new TypeInstance(TypeEnum.ERROR);
-	
-	this.printNode(n, argu, false, ret.get_type()); 
-	--this.offset;
+        TypeInstance ret = (stmt.equal_type(ret_type) &&
+                            stmt.get_type() == TypeEnum.CHECK) ?
+            new TypeInstance(TypeEnum.CHECK) :
+            new TypeInstance(TypeEnum.ERROR);
+
+        this.printNode(n, argu, false, ret.get_type());
+        --this.offset;
         return ret;
     }
 
@@ -319,19 +319,19 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f1 -> ( FormalParameterRest() )*
      */
     public TypeInstance visit(FormalParameterList n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance _ret=null;
         TypeInstance para1 = n.f0.accept(this, argu);
         TypeInstance parar = n.f1.accept(this, argu);
         TypeInstance ret = (para1.get_type() == TypeEnum.CHECK &&
-			    parar.get_type() == TypeEnum.CHECK) ?
-	    new TypeInstance(TypeEnum.CHECK) :
-	    new TypeInstance(TypeEnum.ERROR);
-	
-	this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+                            parar.get_type() == TypeEnum.CHECK) ?
+            new TypeInstance(TypeEnum.CHECK) :
+            new TypeInstance(TypeEnum.ERROR);
+
+        this.printNode(n, argu, false, ret.get_type());
+        --this.offset;
         return ret;
     }
 
@@ -340,14 +340,14 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f1 -> Identifier()
      */
     public TypeInstance visit(FormalParameter n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance ret = n.f0.accept(this, argu);
         n.f1.accept(this, argu);
-	
-	this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+
+        this.printNode(n, argu, false, ret.get_type());
+        --this.offset;
         return ret;
     }
 
@@ -356,14 +356,14 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f1 -> FormalParameter()
      */
     public TypeInstance visit(FormalParameterRest n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         n.f0.accept(this, argu);
         TypeInstance ret = n.f1.accept(this, argu);
-	
-	this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+
+        this.printNode(n, argu, false, ret.get_type());
+        --this.offset;
         return ret;
     }
 
@@ -374,13 +374,13 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      *               | Identifier()
      */
     public TypeInstance visit(Type n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
-	TypeInstance ret =  n.f0.accept(this, argu);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
+        TypeInstance ret =  n.f0.accept(this, argu);
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
@@ -390,16 +390,13 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f2 -> "]"
      */
     public TypeInstance visit(ArrayType n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
-        n.f0.accept(this, argu);
-        n.f1.accept(this, argu);
-        n.f2.accept(this, argu);
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance ret = new TypeInstance(TypeEnum.int_array);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
@@ -407,12 +404,13 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f0 -> "boolean"
      */
     public TypeInstance visit(BooleanType n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance ret =  new TypeInstance(TypeEnum.bool);
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
@@ -420,13 +418,13 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f0 -> "int"
      */
     public TypeInstance visit(IntegerType n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance ret =  new TypeInstance(TypeEnum.integer);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
@@ -439,13 +437,13 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      *               | PrintStatement()
      */
     public TypeInstance visit(Statement n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance ret =  n.f0.accept(this, argu);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
@@ -455,28 +453,32 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f2 -> "}"
      */
     public TypeInstance visit(Block n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         n.f0.accept(this, argu);
         TypeInstance ret = n.f1.accept(this, argu);
         n.f2.accept(this, argu);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
+    // FIXME FIXME FIXME
+    // Given we only have a few types, what is a subtype of what?
     /**
+     * [23]: Expression is a subtype of identifier, and e typechecks*
+     *
      * f0 -> Identifier()
      * f1 -> "="
      * f2 -> Expression()
      * f3 -> ";"
      */
     public TypeInstance visit(AssignmentStatement n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance lhs = n.f0.accept(this, argu);
         n.f1.accept(this, argu);
         TypeInstance rhs = n.f2.accept(this, argu);
@@ -484,25 +486,29 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
         TypeInstance ret = (lhs.equal_type(rhs)) ?
             new TypeInstance(TypeEnum.CHECK) :
             new TypeInstance(TypeEnum.ERROR);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
+    // FIXME (this may be done)
     /**
+     * [24]: Identifier is an integer array, expressions are both integers
+     *
      * f0 -> Identifier()
      * f1 -> "["
-     * f2 -> Expression() //int
+     * f2 -> Expression()
      * f3 -> "]"
      * f4 -> "="
-     * f5 -> Expression() //int
+     * f5 -> Expression()
      * f6 -> ";"
      */
     public TypeInstance visit(ArrayAssignmentStatement n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
+        TypeInstance id = new TypeInstance(argu.get(n.f0.f0.tokenImage));
         n.f0.accept(this, argu);
         n.f1.accept(this, argu);
         TypeInstance index = n.f2.accept(this, argu);
@@ -510,17 +516,20 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
         n.f4.accept(this, argu);
         TypeInstance value = n.f5.accept(this, argu);
         n.f6.accept(this, argu);
-        TypeInstance ret =  (index.get_type() == TypeEnum.integer &&
+        TypeInstance ret =  (id.get_type() == TypeEnum.int_array &&
+                             index.get_type() == TypeEnum.integer &&
                              value.get_type() == TypeEnum.integer) ?
             new TypeInstance(TypeEnum.CHECK) :
             new TypeInstance(TypeEnum.ERROR);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
     /**
+     * DONE [25]: Expression is a bool, both statements type-check
+     *
      * f0 -> "if"
      * f1 -> "("
      * f2 -> Expression()
@@ -530,9 +539,9 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f6 -> Statement()
      */
     public TypeInstance visit(IfStatement n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         n.f0.accept(this, argu);
         n.f1.accept(this, argu);
         TypeInstance expr = n.f2.accept(this, argu);
@@ -545,14 +554,16 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
                             stmt1.get_type() == TypeEnum.CHECK) ?
             new TypeInstance(TypeEnum.CHECK) :
             new TypeInstance(TypeEnum.ERROR);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
 
     }
 
     /**
+     * DONE [26]: Expression is a bool, statement type-checks
+     *
      * f0 -> "while"
      * f1 -> "("
      * f2 -> Expression()
@@ -560,9 +571,9 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f4 -> Statement()
      */
     public TypeInstance visit(WhileStatement n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         n.f0.accept(this, argu);
         n.f1.accept(this, argu);
         TypeInstance expr = n.f2.accept(this, argu);
@@ -572,13 +583,15 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
                             stmt.get_type() == TypeEnum.CHECK) ?
             new TypeInstance(TypeEnum.CHECK) :
             new TypeInstance(TypeEnum.ERROR);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
     /**
+     * DONE [27]: Expression is an integer
+     *
      * f0 -> "System.out.println"
      * f1 -> "("
      * f2 -> Expression()
@@ -586,9 +599,9 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f4 -> ";"
      */
     public TypeInstance visit(PrintStatement n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         n.f0.accept(this, argu);
         n.f1.accept(this, argu);
         TypeInstance ret = n.f2.accept(this, argu);
@@ -597,9 +610,9 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
         ret = (ret.get_type() == TypeEnum.integer) ?
             new TypeInstance(TypeEnum.CHECK) :
             new TypeInstance(TypeEnum.ERROR);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
@@ -615,25 +628,27 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      *               | PrimaryExpression()
      */
     public TypeInstance visit(Expression n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance ret = n.f0.accept(this, argu);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
     /**
-     * f0 -> PrimaryExpressionppp()
+     * DONE [28]: If expressions are both booleans, return is a boolean
+     *
+     * f0 -> PrimaryExpression()
      * f1 -> "&&"
      * f2 -> PrimaryExpression()
      */
     public TypeInstance visit(AndExpression n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance oper1 = n.f0.accept(this, argu);
         n.f1.accept(this, argu);
         TypeInstance oper2 = n.f2.accept(this, argu);
@@ -641,21 +656,23 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
                             oper2.get_type() == TypeEnum.bool) ?
             new TypeInstance(TypeEnum.bool) :
             new TypeInstance(TypeEnum.ERROR);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
     /**
+     * DONE [29]: If expressions are both integers, return is a boolean
+     *
      * f0 -> PrimaryExpression()
      * f1 -> "<"
      * f2 -> PrimaryExpression()
      */
     public TypeInstance visit(CompareExpression n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance oper1 = n.f0.accept(this, argu);
         n.f1.accept(this, argu);
         TypeInstance oper2 = n.f2.accept(this, argu);
@@ -663,21 +680,23 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
                             oper2.get_type() == TypeEnum.integer) ?
             new TypeInstance(TypeEnum.bool) :
             new TypeInstance(TypeEnum.ERROR);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
     /**
+     * DONE [30]: If expressions are both integers, return is an integer
+     *
      * f0 -> PrimaryExpression()
      * f1 -> "+"
      * f2 -> PrimaryExpression()
      */
     public TypeInstance visit(PlusExpression n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance oper1 = n.f0.accept(this, argu);
         n.f1.accept(this, argu);
         TypeInstance oper2 = n.f2.accept(this, argu);
@@ -685,21 +704,23 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
                             oper2.get_type() == TypeEnum.integer) ?
             new TypeInstance(TypeEnum.integer) :
             new TypeInstance(TypeEnum.ERROR);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
     /**
+     * DONE [31]: If expressions are both integers, return is an integer
+     *
      * f0 -> PrimaryExpression()
      * f1 -> "-"
      * f2 -> PrimaryExpression()
      */
     public TypeInstance visit(MinusExpression n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance oper1 = n.f0.accept(this, argu);
         n.f1.accept(this, argu);
         TypeInstance oper2 = n.f2.accept(this, argu);
@@ -707,21 +728,23 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
                             oper2.get_type() == TypeEnum.integer) ?
             new TypeInstance(TypeEnum.integer) :
             new TypeInstance(TypeEnum.ERROR);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
     /**
+     * DONE [32]: If expressions are both integers, return is an integer
+     *
      * f0 -> PrimaryExpression()
      * f1 -> "*"
      * f2 -> PrimaryExpression()
      */
     public TypeInstance visit(TimesExpression n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance oper1 = n.f0.accept(this, argu);
         n.f1.accept(this, argu);
         TypeInstance oper2 = n.f2.accept(this, argu);
@@ -729,22 +752,25 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
                             oper2.get_type() == TypeEnum.integer) ?
             new TypeInstance(TypeEnum.integer) :
             new TypeInstance(TypeEnum.ERROR);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
     /**
+     * DONE [33]: If expr1 is an integer array and expr2 is an int,
+     * return is an int
+     *
      * f0 -> PrimaryExpression()
      * f1 -> "["
      * f2 -> PrimaryExpression()
      * f3 -> "]"
      */
     public TypeInstance visit(ArrayLookup n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance array = n.f0.accept(this, argu);
         n.f1.accept(this, argu);
         TypeInstance index = n.f2.accept(this, argu);
@@ -753,33 +779,38 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
                             index.get_type() == TypeEnum.integer) ?
             new TypeInstance(TypeEnum.integer) :
             new TypeInstance(TypeEnum.ERROR);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
     /**
+     * DONE [34]: If expr1 is an integer array, return is an int
+     *
      * f0 -> PrimaryExpression()
      * f1 -> "."
      * f2 -> "length"
      */
     public TypeInstance visit(ArrayLength n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance ret = n.f0.accept(this, argu);
         n.f1.accept(this, argu);
         n.f2.accept(this, argu);
         ret = (ret.get_type() == TypeEnum.int_array) ? new TypeInstance(TypeEnum.integer) :
             new TypeInstance(TypeEnum.ERROR);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
+    // FIXME FIXME FIXME
     /**
+     *  [35]:
+     *
      * f0 -> PrimaryExpression()
      * f1 -> "."
      * f2 -> Identifier()
@@ -788,9 +819,9 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f5 -> ")"
      */
     public TypeInstance visit(MessageSend n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance _ret=null;
         n.f0.accept(this, argu);
         n.f1.accept(this, argu);
@@ -798,7 +829,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
         n.f3.accept(this, argu);
         n.f4.accept(this, argu);
         n.f5.accept(this, argu);
-	--this.offset;
+        --this.offset;
         return _ret;
     }
 
@@ -808,14 +839,19 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f1 -> ( ExpressionRest() )*
      */
     public TypeInstance visit(ExpressionList n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
-	TypeInstance _ret=null;
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance expr1 = n.f0.accept(this, argu);
         TypeInstance exprr =  n.f1.accept(this, argu);
-	--this.offset;
-        return _ret;
+        TypeInstance ret = (expr1.get_type() == TypeEnum.CHECK &&
+                            exprr.get_type() == TypeEnum.CHECK) ?
+            new TypeInstance(TypeEnum.CHECK) :
+            new TypeInstance(TypeEnum.ERROR);
+
+        this.printNode(n, argu, false, ret.get_type());
+        --this.offset;
+        return ret;
     }
 
     /**
@@ -823,14 +859,14 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f1 -> Expression()
      */
     public TypeInstance visit(ExpressionRest n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         n.f0.accept(this, argu);
         TypeInstance ret = n.f1.accept(this, argu);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
@@ -846,83 +882,97 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      *               | BracketExpression()
      */
     public TypeInstance visit(PrimaryExpression n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         TypeInstance ret = n.f0.accept(this, argu);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
     /**
+     * DONE [36]: return is an int
+     *
+     *
      * f0 -> <INTEGER_LITERAL>
      */
     public TypeInstance visit(IntegerLiteral n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         this.printNode(n, argu, false, TypeEnum.integer);
-	--this.offset;
+        --this.offset;
         return new TypeInstance(TypeEnum.integer);
     }
 
     /**
+     * DONE [37]: return is a bool
+     *
      * f0 -> "true"
      */
     public TypeInstance visit(TrueLiteral n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         this.printNode(n, argu, false, TypeEnum.bool);
-	--this.offset;
+        --this.offset;
         return new TypeInstance(TypeEnum.bool);
     }
 
     /**
+     * DONE [38]: return is a bool
+     *
      * f0 -> "false"
      */
     public TypeInstance visit(FalseLiteral n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         this.printNode(n, argu, false, TypeEnum.bool);
-	--this.offset;
+        --this.offset;
         return new TypeInstance(TypeEnum.bool);
     }
 
+    // FIXME
     /**
+     * [39]: id is a symbol in the current domain, return is id's type
+     *
      * f0 -> <IDENTIFIER>
      */
     public TypeInstance visit(Identifier n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
+        TypeInstance ret = new TypeInstance(argu.get(n.f0.tokenImage));
 
-	TypeInstance ret = new TypeInstance(argu.get(n.f0.tokenImage));
-	
-        this.printNode(n, argu, false, TypeEnum.CHECK);
-	--this.offset;
-        return new TypeInstance(TypeEnum.CHECK);
+        this.printNode(n, argu, false, ret.get_type());
+        --this.offset;
+        return ret;
     }
 
-    //FIXME
+    //FIXME FIXME FIXME
     /**
+     * [40]: method exists? but where is the token?
+     *
      * f0 -> "this"
      */
     public TypeInstance visit(ThisExpression n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         n.f0.accept(this, argu);
-	TypeInstance ret = new TypeInstance(TypeEnum.CHECK);
-	
-	this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        TypeInstance ret = new TypeInstance(TypeEnum.CHECK);
+
+        this.printNode(n, argu, false, ret.get_type());
+        --this.offset;
         return ret;
     }
 
     /**
+     * DONE [41]: if expression is an integer, return is an int array
+     *
      * f0 -> "new"
      * f1 -> "int"
      * f2 -> "["
@@ -930,9 +980,9 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f4 -> "]"
      */
     public TypeInstance visit(ArrayAllocationExpression n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         n.f0.accept(this, argu);
         TypeInstance ret = n.f1.accept(this, argu);
         n.f2.accept(this, argu);
@@ -940,63 +990,70 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
         n.f4.accept(this, argu);
         ret = (ret.get_type() == TypeEnum.integer) ? new TypeInstance(TypeEnum.int_array) :
             new TypeInstance(TypeEnum.ERROR);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
+    // FIXME FIXME FIXME
     /**
+     * [42]:
+     *
      * f0 -> "new"
      * f1 -> Identifier()
      * f2 -> "("
      * f3 -> ")"
      */
     public TypeInstance visit(AllocationExpression n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         n.f0.accept(this, argu);
         TypeInstance ret = n.f1.accept(this, argu);
         n.f2.accept(this, argu);
         n.f3.accept(this, argu);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }
 
     /**
+     * [43]: if expression is a boolean, return is a boolean
+     *
      * f0 -> "!"
      * f1 -> Expression()
      */
     public TypeInstance visit(NotExpression n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         n.f0.accept(this, argu);
         TypeInstance ret = n.f1.accept(this, argu);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return (ret.get_type() == TypeEnum.bool) ? ret : new TypeInstance(TypeEnum.ERROR);
     }
 
     /**
+     * [44]: if e is a type, return is that same type
+     *
      * f0 -> "("
      * f1 -> Expression()
      * f2 -> ")"
      */
     public TypeInstance visit(BracketExpression n, HashMap<String,TypeEnum> argu) {
-	++this.offset;
-	this.printNode(n, argu, true, null);
-	
+        ++this.offset;
+        this.printNode(n, argu, true, null);
+
         n.f0.accept(this, argu);
         TypeInstance ret = n.f1.accept(this, argu);
         n.f2.accept(this, argu);
-	
+
         this.printNode(n, argu, false, ret.get_type());
-	--this.offset;
+        --this.offset;
         return ret;
     }