SymbolTable to separate library, Class/Method Instances

16 files changed, 479 insertions, 275 deletions

diff --git a/Typecheck.java b/Typecheck.java
index 6d45598..d2639f5 100644
--- a/Typecheck.java
+++ b/Typecheck.java
@@ -1,10 +1,10 @@
-// Helper for HW2/CS453.
 import java.io.*;
 import visitor.*;
 import syntaxtree.*;
 import java.util.*;
-// Files are stored in the typecheck directory/package.
+import st.*;
 import typecheck.library.*;
+import misc.*;
 
 public class Typecheck {
     public static void main(String[] args) {
@@ -16,15 +16,15 @@ public class Typecheck {
             // GJDepthFirst<R,A>. R=Void, A=String.
             PPrinter<Void,String> pp = new PPrinter<Void,String>();
             root.accept(pp, "");
-            Utilities.print_filter("===================================================", true);
+            PrintFilter.print("===================================================", true);
 
             // // Build the symbol table. Top-down visitor, inherits from
             // // GJDepthFirst<R,A>. R=Void, A=Integer.
             SymTableVis<Void,Integer> pv =
                 new SymTableVis<Void,Integer>();
             root.accept(pv, 0);
-            HashMap<String, TypeInstance> symt = pv.symt;
-            Utilities.print_filter("===================================================", true);
+            HashMap<String, AbstractInstance> symt = pv.symt;
+            PrintFilter.print("===================================================", true);
 
             // Do type checking. Bottom-up visitor, also inherits from
             // GJDepthFirst. Visit functions return MyTpe (=R), and
diff --git a/typecheck/library/PPrinter.java b/misc/PPrinter.java
index e8e1b15..eff2357 100644
--- a/typecheck/library/PPrinter.java
+++ b/misc/PPrinter.java
@@ -1,4 +1,4 @@
-package typecheck.library;
+package misc;
 
 import syntaxtree.*;
 import visitor.*;
@@ -14,8 +14,8 @@ public class PPrinter<R,A> extends GJDepthFirst<R,A> {
 
     private void printNode(Node n, A argu) {
         for (int i=0; i < this.offset; ++i)
-            Utilities.print_filter(".", false);
-        Utilities.print_filter(n.getClass().getSimpleName(), true);
+            PrintFilter.print(".", false);
+        PrintFilter.print(n.getClass().getSimpleName(), true);
         ++this.offset;
     }
 
@@ -726,10 +726,10 @@ public class PPrinter<R,A> extends GJDepthFirst<R,A> {
 
     public R visit(NodeToken n, A argu) {
         for (int i=0; i < this.offset; ++i)
-            Utilities.print_filter(".", false);
-        Utilities.print_filter(n.getClass().getSimpleName() +
-                               " => " +
-                               n.toString(), true);
+            PrintFilter.print(".", false);
+        PrintFilter.print(n.getClass().getSimpleName() +
+			  " => " +
+			  n.toString(), true);
         R _ret=null;
         return _ret;
     }
diff --git a/misc/PrintFilter.java b/misc/PrintFilter.java
new file mode 100644
index 0000000..971ef04
--- /dev/null
+++ b/misc/PrintFilter.java
@@ -0,0 +1,15 @@
+package misc;
+
+
+public class PrintFilter {
+
+    public static void print(String message, boolean newline) {
+        boolean debug = true;
+        if (debug) {
+            System.out.print(message);
+            if (newline)
+                System.out.println();
+        }
+    }
+
+}
diff --git a/st/AbstractInstance.java b/st/AbstractInstance.java
new file mode 100644
index 0000000..a7dc8eb
--- /dev/null
+++ b/st/AbstractInstance.java
@@ -0,0 +1,35 @@
+package st;
+
+public abstract class AbstractInstance {
+    protected String name;        // the literal name of the declaration
+    protected TypeEnum type;      // the type of the declaration
+    protected int size;           // the size in memory
+
+    public AbstractInstance(String name, TypeEnum type) {
+        this.type = type;
+        this.name = name;
+    }
+
+    public abstract String toString();
+
+    public boolean equals(AbstractInstance other) {
+        return this.name == other.get_name();
+    }
+
+    public int hashCode() {
+        return this.name.hashCode();
+    }
+
+    public String get_name() {
+        return this.name;
+    }
+
+    public TypeEnum get_type() {
+        return this.type;
+    }
+
+    public int get_size() {
+        return this.size;
+    }
+
+}
diff --git a/st/ClassInstance.java b/st/ClassInstance.java
new file mode 100644
index 0000000..c1b07af
--- /dev/null
+++ b/st/ClassInstance.java
@@ -0,0 +1,37 @@
+package st;
+
+import java.util.ArrayList;
+
+public class ClassInstance extends AbstractInstance {
+    private ArrayList<TypeInstance> attrs;      // the list of class-fields
+    private ArrayList<MethodInstance> mtds;     // the list of methods
+    private String ext;                         // the name of the extended class (null if none)
+
+    public ClassInstance(String name) {
+        super(name, TypeEnum.classname);
+        this.ext = null;
+    }
+
+    public ClassInstance(String name, String ext) {
+        super(name, TypeEnum.classname);
+        this.ext = ext;
+    }
+
+    public String toString() {
+        return this.name + ":" + this.type + "(" +
+            this.ext + ")";
+    }
+
+    public void add_attribute(TypeInstance attr) {
+        this.attrs.add(attr);
+    }
+
+    public void add_attribute(MethodInstance mtd) {
+        this.mtds.add(mtd);
+    }
+
+    public String get_extend() {
+        return this.ext;
+    }
+
+}
diff --git a/st/MethodInstance.java b/st/MethodInstance.java
new file mode 100644
index 0000000..c0082af
--- /dev/null
+++ b/st/MethodInstance.java
@@ -0,0 +1,24 @@
+package st;
+
+import java.util.ArrayList;
+
+public class MethodInstance extends AbstractInstance {
+    private ArrayList<TypeEnum> args;   // the list of arguments
+    private TypeEnum rtrn;              // the returned type
+
+    public MethodInstance(String name, TypeEnum rtrn) {
+        super(name, TypeEnum.method);
+        this.args = new ArrayList<>();
+        this.rtrn = rtrn;
+    }
+
+    public String toString() {
+        return name + ":" + type + "[" +
+            this.rtrn + "]";
+    }
+
+    public void add_argument(TypeEnum arg) {
+        this.args.add(arg);
+    }
+
+}
diff --git a/st/SymTableVis.java b/st/SymTableVis.java
new file mode 100644
index 0000000..280a89c
--- /dev/null
+++ b/st/SymTableVis.java
@@ -0,0 +1,219 @@
+package st;
+
+import syntaxtree.*;
+import visitor.*;
+import java.util.*;
+import misc.*;
+
+/**
+ * Provides default methods which visit each node in the tree in depth-first
+ * order.  Your visitors may extend this class.
+ */
+public class SymTableVis<R,A> extends GJDepthFirst<R,A> {
+
+    public HashMap<String,AbstractInstance> symt = new HashMap<>();
+
+    /**
+     * f0 -> "class"
+     * f1 -> Identifier()
+     * f2 -> "{"
+     * f3 -> "public"
+     * f4 -> "static"
+     * f5 -> "void"
+     * f6 -> "main"
+     * f7 -> "("
+     * f8 -> "String"
+     * f9 -> "["
+     * f10 -> "]"
+     * f11 -> Identifier()
+     * f12 -> ")"
+     * f13 -> "{"
+     * f14 -> ( VarDeclaration() )*
+     * f15 -> ( Statement() )*
+     * f16 -> "}"
+     * f17 -> "}"
+     */
+    public R visit(MainClass n, A argu) {
+
+        PrintFilter.print("Processing main", true);
+
+        String id = n.f1.f0.tokenImage;
+
+        ClassInstance type = new ClassInstance(id);
+        PrintFilter.print("Inserting " + id + " => " + type, true);
+        symt.put(id, type);
+
+        n.f0.accept(this, argu);
+        n.f1.accept(this, argu);
+        n.f2.accept(this, argu);
+        n.f3.accept(this, argu);
+        n.f4.accept(this, argu);
+        n.f5.accept(this, argu);
+        n.f6.accept(this, argu);
+        n.f7.accept(this, argu);
+        n.f8.accept(this, argu);
+        n.f9.accept(this, argu);
+        n.f10.accept(this, argu);
+        n.f11.accept(this, argu);
+        n.f12.accept(this, argu);
+        n.f13.accept(this, argu);
+        n.f14.accept(this, argu);
+        n.f15.accept(this, argu);
+        n.f16.accept(this, argu);
+        n.f17.accept(this, argu);
+        return null;
+
+    }
+
+    /**
+     * f0 -> "class"
+     * f1 -> Identifier()
+     * f2 -> "{"
+     * f3 -> ( VarDeclaration() )*
+     * f4 -> ( MethodDeclaration() )*
+     * f5 -> "}"
+     */
+    public R visit(ClassDeclaration n, A argu) {
+
+        PrintFilter.print("Processing class", true);
+
+        String id = n.f1.f0.tokenImage;
+
+        ClassInstance type = new ClassInstance(id);
+        PrintFilter.print("Inserting " + id + " => " + type, true);
+        // Safe?
+
+        symt.put(id, type);
+
+        n.f0.accept(this, argu);
+        n.f1.accept(this, argu);
+        n.f2.accept(this, argu);
+        n.f3.accept(this, argu);
+        n.f4.accept(this, argu);
+        n.f5.accept(this, argu);
+        return null;
+
+    }
+
+    /**
+     * f0 -> "class"
+     * f1 -> Identifier()
+     * f2 -> "extends"
+     * f3 -> Identifier()
+     * f4 -> "{"
+     * f5 -> ( VarDeclaration() )*
+     * f6 -> ( MethodDeclaration() )*
+     * f7 -> "}"
+     */
+    public R visit(ClassExtendsDeclaration n, A argu) {
+        PrintFilter.print("Processing class", true);
+
+        String id = n.f1.f0.tokenImage;
+        String ext = n.f3.f0.tokenImage;
+
+        ClassInstance type = new ClassInstance(id, ext);
+        PrintFilter.print("Inserting " + id + " => " + type +
+                          "(" + ext + ")", true);
+
+        symt.put(id, type);
+
+        n.f0.accept(this, argu);
+        n.f1.accept(this, argu);
+        n.f2.accept(this, argu);
+        n.f3.accept(this, argu);
+        n.f4.accept(this, argu);
+        n.f5.accept(this, argu);
+        n.f6.accept(this, argu);
+        n.f7.accept(this, argu);
+        return null;
+    }
+
+
+    /**
+     * f0 -> Type()
+     * f1 -> Identifier()
+     * f2 -> ";"
+     */
+    public R visit(VarDeclaration n, A argu) {
+
+        PrintFilter.print("Processing declaration", true);
+
+        String id = n.f1.f0.tokenImage;
+        TypeEnum rtrn = TypeEnum.ERROR;
+        switch (n.f0.f0.which) {
+        case 0:
+            rtrn = TypeEnum.intarray; break;
+        case 1:
+            rtrn = TypeEnum.bool; break;
+        case 2:
+            rtrn = TypeEnum.integer; break;
+        case 3:
+            rtrn = TypeEnum.classname; break;
+        default:
+            PrintFilter.print("Unsupported case", true);
+        }
+
+        TypeInstance type = new TypeInstance(id, rtrn);
+        PrintFilter.print("Inserting " + type, true);
+        symt.put(id, type);
+
+        n.f0.accept(this, argu);
+        n.f1.accept(this, argu);
+        n.f2.accept(this, argu);
+        return null;
+    }
+
+    /**
+     * f0 -> "public"
+     * f1 -> Type()
+     * f2 -> Identifier()
+     * f3 -> "("
+     * f4 -> ( FormalParameterList() )?
+     * f5 -> ")"
+     * f6 -> "{"
+     * f7 -> ( VarDeclaration() )*
+     * f8 -> ( Statement() )*
+     * f9 -> "return"
+     * f10 -> Expression()
+     * f11 -> ";"
+     * f12 -> "}"
+     */
+    public R visit(MethodDeclaration n, A argu) {
+
+        PrintFilter.print("Processing method", true);
+
+        String id = n.f2.f0.tokenImage;
+
+        TypeEnum rtrn = TypeEnum.ERROR;
+        switch (n.f1.f0.which) {
+        case 0:
+            rtrn = TypeEnum.intarray; break;
+        case 1:
+            rtrn = TypeEnum.bool; break;
+        case 2:
+            rtrn = TypeEnum.integer; break;
+        default:
+            PrintFilter.print("Unsupported case", true);
+        }
+
+        MethodInstance type = new MethodInstance(id, rtrn);
+        PrintFilter.print("Inserting " + type, true);
+        symt.put(id, type);
+
+        n.f0.accept(this, argu);
+        n.f1.accept(this, argu);
+        n.f2.accept(this, argu);
+        n.f3.accept(this, argu);
+        n.f4.accept(this, argu);
+        n.f5.accept(this, argu);
+        n.f6.accept(this, argu);
+        n.f7.accept(this, argu);
+        n.f8.accept(this, argu);
+        n.f9.accept(this, argu);
+        n.f10.accept(this, argu);
+        n.f11.accept(this, argu);
+        n.f12.accept(this, argu);
+        return null;
+    }
+
+}
diff --git a/st/TypeEnum.java b/st/TypeEnum.java
new file mode 100644
index 0000000..f6fc6ae
--- /dev/null
+++ b/st/TypeEnum.java
@@ -0,0 +1,5 @@
+package st;
+
+public enum TypeEnum {
+    classname, method, intarray, bool, integer, CHECK, ERROR
+}
diff --git a/st/TypeInstance.java b/st/TypeInstance.java
new file mode 100644
index 0000000..13947ae
--- /dev/null
+++ b/st/TypeInstance.java
@@ -0,0 +1,32 @@
+package st;
+
+public class TypeInstance extends AbstractInstance {
+
+    public TypeInstance(String name, TypeEnum type) {
+        super(name, type);
+    }
+
+    public String toString() {
+        return this.name + ":" + this.type;
+    }
+
+    public boolean same_type(TypeInstance other) {
+        /**
+         * Given a TypeInstance object other,
+         * returns true if other object
+         * is the same type as this one.
+         *
+         * We can say two types are equal, as
+         * long as they are not equal on a
+         * type error!
+         */
+
+        return this.type != TypeEnum.ERROR &&
+            this.type == other.get_type();
+    }
+
+    public boolean has_checked() {
+        return type != TypeEnum.ERROR;
+    }
+
+}
diff --git a/typecheck/library/SymTableVis.java b/typecheck/library/SymTableVis.java
deleted file mode 100644
index 615b1c9..0000000
--- a/typecheck/library/SymTableVis.java
+++ /dev/null
@@ -1,101 +0,0 @@
-package typecheck.library;
-
-import syntaxtree.*;
-import visitor.*;
-import java.util.*;
-
-/**
- * Provides default methods which visit each node in the tree in depth-first
- * order.  Your visitors may extend this class.
- */
-public class SymTableVis<R,A> extends GJDepthFirst<R,A> {
-
-    public HashMap<String,TypeInstance> symt = new HashMap<>();
-
-    /**
-     * f0 -> "class"
-     * f1 -> Identifier()
-     * f2 -> "{"
-     * f3 -> "public"
-     * f4 -> "static"
-     * f5 -> "void"
-     * f6 -> "main"
-     * f7 -> "("
-     * f8 -> "String"
-     * f9 -> "["
-     * f10 -> "]"
-     * f11 -> Identifier()
-     * f12 -> ")"
-     * f13 -> "{"
-     * f14 -> ( VarDeclaration() )*
-     * f15 -> ( Statement() )*
-     * f16 -> "}"
-     * f17 -> "}"
-     */
-    public R visit(MainClass n, A argu) {
-
-        n.f1.accept(this, argu);
-        n.f11.accept(this, argu);
-        n.f14.accept(this, argu);
-        n.f15.accept(this, argu);
-
-        Utilities.print_filter("Processing main", true);
-
-        String id = n.f1.f0.tokenImage;
-
-        TypeInstance type = new TypeInstance(id, TypeEnum.classname);
-        Utilities.print_filter("Inserting " + id + " => " + type, true);
-        symt.put(id, type);
-
-        return null;
-
-    }
-
-    /**
-     * f0 -> Type()
-     * f1 -> Identifier()
-     * f2 -> ";"
-     */
-    public R visit(VarDeclaration n, A argu) {
-
-        Utilities.print_filter("Processing declaration", true);
-
-        String id = n.f1.f0.tokenImage;
-        TypeInstance type = new TypeInstance("ERROR", TypeEnum.ERROR);
-        switch (n.f0.f0.which) {
-        case 0:
-            type = new TypeInstance("int_array", TypeEnum.int_array); break;
-        case 1:
-            type = new TypeInstance("bool", TypeEnum.bool); break;
-        case 2:
-            type = new TypeInstance("int", TypeEnum.integer); break;
-        case 3:
-            type = new TypeInstance(id, TypeEnum.classname); break;
-        default:
-            Utilities.print_filter("Unsupported case", true);
-        }
-
-        Utilities.print_filter("Inserting " + id + " => " + type, true);
-        // Safe?
-        symt.put(id, type);
-
-        return null;
-    }
-
-    public R visit(ClassDeclaration n, A argu) {
-
-        Utilities.print_filter("Processing class", true);
-
-        String id = n.f1.f0.tokenImage;
-
-        TypeInstance type = new TypeInstance(id, TypeEnum.classname);
-        Utilities.print_filter("Inserting " + id + " => " + type, true);
-        // Safe?
-        symt.put(id, type);
-
-        return null;
-
-    }
-
-
-}
diff --git a/typecheck/library/TypeCheckSimp.java b/typecheck/library/TypeCheckSimp.java
index b4844a1..3d262fd 100644
--- a/typecheck/library/TypeCheckSimp.java
+++ b/typecheck/library/TypeCheckSimp.java
@@ -2,34 +2,36 @@ package typecheck.library;
 
 import syntaxtree.*;
 import visitor.*;
+import st.*;
+import misc.*;
 import java.util.*;
 
 /**
  * Provides default methods which visit each node in the tree in depth-first
  * order.  Your visitors may extend this class.
  */
-public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,TypeInstance>> {
+public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,AbstractInstance>> {
 
     private int offset;
 
-    private void printNode(Node n, HashMap<String,TypeInstance> argu, boolean enter, TypeEnum consensus) {
+    private void printNode(Node n, HashMap<String,AbstractInstance> argu, boolean enter, TypeEnum consensus) {
         for (int i=0; i < this.offset; ++i)
-            Utilities.print_filter(".", false);
+            PrintFilter.print(".", false);
         if (enter)
-            Utilities.print_filter("Visiting ", false);
+            PrintFilter.print("Visiting ", false);
         else
-            Utilities.print_filter("Leaving ", false);
-        Utilities.print_filter(n.getClass().getSimpleName(), false);
+            PrintFilter.print("Leaving ", false);
+        PrintFilter.print(n.getClass().getSimpleName(), false);
         if (!enter) {
             if (consensus == TypeEnum.ERROR)
-                Utilities.print_filter(" did not type check.", false);
+                PrintFilter.print(" did not type check.", false);
             else
-                Utilities.print_filter(" found type " + consensus, false);
+                PrintFilter.print(" found type " + consensus, false);
         }
-        Utilities.print_filter("", true);
+        PrintFilter.print("", true);
     }
 
-    public TypeInstance visit(NodeList n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(NodeList n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -48,7 +50,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
         return ret;
     }
 
-    public TypeInstance visit(NodeListOptional n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(NodeListOptional n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -72,7 +74,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
     }
 
     // FIXME
-    public TypeInstance visit(NodeOptional n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(NodeOptional n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -88,7 +90,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
         return ret;
     }
 
-    public TypeInstance visit(NodeSequence n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(NodeSequence n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -106,13 +108,13 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
         return ret;
     }
 
-    public TypeInstance visit(NodeToken n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(NodeToken n, HashMap<String,AbstractInstance> argu) {
         // A fixed string token. '⌣'
         for (int i=0; i < this.offset; ++i)
-            Utilities.print_filter(".", false);
-        Utilities.print_filter("Leaving " + n.getClass().getSimpleName() +
-                               " => " +
-                               n.toString(), true);
+            PrintFilter.print(".", false);
+        PrintFilter.print("Leaving " + n.getClass().getSimpleName() +
+                          " => " +
+                          n.toString(), true);
         return null;
     }
 
@@ -125,7 +127,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f1 -> ( TypeDeclaration() )*
      * f2 -> <EOF>
      */
-    public TypeInstance visit(Goal n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(Goal n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -158,7 +160,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f16 -> "}"
      * f17 -> "}"
      */
-    public TypeInstance visit(MainClass n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(MainClass n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -188,9 +190,9 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
 
     /**
      * f0 -> ClassDeclaration()
-     *                               | ClassExtendsDeclaration()
+     *     | ClassExtendsDeclaration()
      */
-    public TypeInstance visit(TypeDeclaration n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(TypeDeclaration n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -209,7 +211,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f4 -> ( MethodDeclaration() )*
      * f5 -> "}"
      */
-    public TypeInstance visit(ClassDeclaration n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(ClassDeclaration n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -240,7 +242,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f6 -> ( MethodDeclaration() )*
      * f7 -> "}"
      */
-    public TypeInstance visit(ClassExtendsDeclaration n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(ClassExtendsDeclaration n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -269,7 +271,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f1 -> Identifier()
      * f2 -> ";"
      */
-    public TypeInstance visit(VarDeclaration n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(VarDeclaration n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -298,7 +300,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f11 -> ";"
      * f12 -> "}"
      */
-    public TypeInstance visit(MethodDeclaration n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(MethodDeclaration n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -315,7 +317,7 @@ 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) &&
+        TypeInstance ret = (stmt.same_type(ret_type) &&
                             stmt.has_checked()) ?
             new TypeInstance(null, TypeEnum.CHECK) :
             new TypeInstance(null, TypeEnum.ERROR);
@@ -329,7 +331,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f0 -> FormalParameter()
      * f1 -> ( FormalParameterRest() )*
      */
-    public TypeInstance visit(FormalParameterList n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(FormalParameterList n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -350,7 +352,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f0 -> Type()
      * f1 -> Identifier()
      */
-    public TypeInstance visit(FormalParameter n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(FormalParameter n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -366,7 +368,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f0 -> ","
      * f1 -> FormalParameter()
      */
-    public TypeInstance visit(FormalParameterRest n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(FormalParameterRest n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -380,15 +382,15 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
 
     /**
      * f0 -> ArrayType()
-     *                               | BooleanType()
-     *                               | IntegerType()
-     *                               | Identifier()
+     *     | BooleanType()
+     *     | IntegerType()
+     *     | Identifier()
      */
-    public TypeInstance visit(Type n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(Type n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
-        TypeInstance ret =      n.f0.accept(this, argu);
+        TypeInstance ret = n.f0.accept(this, argu);
 
         this.printNode(n, argu, false, ret.get_type());
         --this.offset;
@@ -400,11 +402,11 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f1 -> "["
      * f2 -> "]"
      */
-    public TypeInstance visit(ArrayType n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(ArrayType n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
-        TypeInstance ret = new TypeInstance(null, TypeEnum.int_array);
+        TypeInstance ret = new TypeInstance(null, TypeEnum.intarray);
 
         this.printNode(n, argu, false, ret.get_type());
         --this.offset;
@@ -414,11 +416,11 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
     /**
      * f0 -> "boolean"
      */
-    public TypeInstance visit(BooleanType n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(BooleanType n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
-        TypeInstance ret =      new TypeInstance(null, TypeEnum.bool);
+        TypeInstance ret = new TypeInstance(null, TypeEnum.bool);
 
         this.printNode(n, argu, false, ret.get_type());
         --this.offset;
@@ -428,7 +430,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
     /**
      * f0 -> "int"
      */
-    public TypeInstance visit(IntegerType n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(IntegerType n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -441,13 +443,13 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
 
     /**
      * f0 -> Block()
-     *                               | AssignmentStatement()
-     *                               | ArrayAssignmentStatement()
-     *                               | IfStatement()
-     *                               | WhileStatement()
-     *                               | PrintStatement()
+     *     | AssignmentStatement()
+     *     | ArrayAssignmentStatement()
+     *     | IfStatement()
+     *     | WhileStatement()
+     *     | PrintStatement()
      */
-    public TypeInstance visit(Statement n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(Statement n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -463,7 +465,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f1 -> ( Statement() )*
      * f2 -> "}"
      */
-    public TypeInstance visit(Block n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(Block n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -486,7 +488,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f2 -> Expression()
      * f3 -> ";"
      */
-    public TypeInstance visit(AssignmentStatement n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(AssignmentStatement n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -494,7 +496,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
         n.f1.accept(this, argu);
         TypeInstance rhs = n.f2.accept(this, argu);
         n.f3.accept(this, argu);
-        TypeInstance ret = (lhs.equal_type(rhs)) ?
+        TypeInstance ret = (lhs.same_type(rhs)) ?
             new TypeInstance(null, TypeEnum.CHECK) :
             new TypeInstance(null, TypeEnum.ERROR);
 
@@ -515,7 +517,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f5 -> Expression()
      * f6 -> ";"
      */
-    public TypeInstance visit(ArrayAssignmentStatement n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(ArrayAssignmentStatement n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -526,7 +528,7 @@ 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 =      (id.get_type() == TypeEnum.int_array &&
+        TypeInstance ret =      (id.get_type() == TypeEnum.intarray &&
                                  index.get_type() == TypeEnum.integer &&
                                  value.get_type() == TypeEnum.integer) ?
             new TypeInstance(null, TypeEnum.CHECK) :
@@ -548,7 +550,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f5 -> "else"
      * f6 -> Statement()
      */
-    public TypeInstance visit(IfStatement n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(IfStatement n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -580,7 +582,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f3 -> ")"
      * f4 -> Statement()
      */
-    public TypeInstance visit(WhileStatement n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(WhileStatement n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -608,7 +610,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f3 -> ")"
      * f4 -> ";"
      */
-    public TypeInstance visit(PrintStatement n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(PrintStatement n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -628,16 +630,16 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
 
     /**
      * f0 -> AndExpression()
-     *                               | CompareExpression()
-     *                               | PlusExpression()
-     *                               | MinusExpression()
-     *                               | TimesExpression()
-     *                               | ArrayLookup()
-     *                               | ArrayLength()
-     *                               | MessageSend()
-     *                               | PrimaryExpression()
+     *     | CompareExpression()
+     *     | PlusExpression()
+     *     | MinusExpression()
+     *     | TimesExpression()
+     *     | ArrayLookup()
+     *     | ArrayLength()
+     *     | MessageSend()
+     *     | PrimaryExpression()
      */
-    public TypeInstance visit(Expression n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(Expression n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -655,7 +657,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f1 -> "&&"
      * f2 -> PrimaryExpression()
      */
-    public TypeInstance visit(AndExpression n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(AndExpression n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -679,7 +681,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f1 -> "<"
      * f2 -> PrimaryExpression()
      */
-    public TypeInstance visit(CompareExpression n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(CompareExpression n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -703,7 +705,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f1 -> "+"
      * f2 -> PrimaryExpression()
      */
-    public TypeInstance visit(PlusExpression n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(PlusExpression n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -727,7 +729,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f1 -> "-"
      * f2 -> PrimaryExpression()
      */
-    public TypeInstance visit(MinusExpression n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(MinusExpression n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -751,7 +753,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f1 -> "*"
      * f2 -> PrimaryExpression()
      */
-    public TypeInstance visit(TimesExpression n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(TimesExpression n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -777,7 +779,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f2 -> PrimaryExpression()
      * f3 -> "]"
      */
-    public TypeInstance visit(ArrayLookup n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(ArrayLookup n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -785,7 +787,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
         n.f1.accept(this, argu);
         TypeInstance index = n.f2.accept(this, argu);
         n.f3.accept(this, argu);
-        TypeInstance ret = (array.get_type() == TypeEnum.int_array &&
+        TypeInstance ret = (array.get_type() == TypeEnum.intarray &&
                             index.get_type() == TypeEnum.integer) ?
             new TypeInstance(null, TypeEnum.integer) :
             new TypeInstance(null, TypeEnum.ERROR);
@@ -802,14 +804,14 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f1 -> "."
      * f2 -> "length"
      */
-    public TypeInstance visit(ArrayLength n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(ArrayLength n, HashMap<String,AbstractInstance> argu) {
         ++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(null, TypeEnum.integer) :
+        ret = (ret.get_type() == TypeEnum.intarray) ? new TypeInstance(null, TypeEnum.integer) :
             new TypeInstance(null, TypeEnum.ERROR);
 
         this.printNode(n, argu, false, ret.get_type());
@@ -828,7 +830,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f4 -> ( ExpressionList() )?
      * f5 -> ")"
      */
-    public TypeInstance visit(MessageSend n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(MessageSend n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -847,7 +849,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f0 -> Expression()
      * f1 -> ( ExpressionRest() )*
      */
-    public TypeInstance visit(ExpressionList n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(ExpressionList n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -867,7 +869,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f0 -> ","
      * f1 -> Expression()
      */
-    public TypeInstance visit(ExpressionRest n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(ExpressionRest n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -881,16 +883,16 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
 
     /**
      * f0 -> IntegerLiteral()
-     *                               | TrueLiteral()
-     *                               | FalseLiteral()
-     *                               | Identifier()
-     *                               | ThisExpression()
-     *                               | ArrayAllocationExpression()
-     *                               | AllocationExpression()
-     *                               | NotExpression()
-     *                               | BracketExpression()
+     *     | TrueLiteral()
+     *     | FalseLiteral()
+     *     | Identifier()
+     *     | ThisExpression()
+     *     | ArrayAllocationExpression()
+     *     | AllocationExpression()
+     *     | NotExpression()
+     *     | BracketExpression()
      */
-    public TypeInstance visit(PrimaryExpression n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(PrimaryExpression n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -907,7 +909,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      *
      * f0 -> <INTEGER_LITERAL>
      */
-    public TypeInstance visit(IntegerLiteral n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(IntegerLiteral n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -921,7 +923,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      *
      * f0 -> "true"
      */
-    public TypeInstance visit(TrueLiteral n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(TrueLiteral n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -935,7 +937,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      *
      * f0 -> "false"
      */
-    public TypeInstance visit(FalseLiteral n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(FalseLiteral n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -950,12 +952,14 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      *
      * f0 -> <IDENTIFIER>
      */
-    public TypeInstance visit(Identifier n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(Identifier n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
         TypeInstance ret = (argu.get(n.f0.tokenImage) != null) ?
-            argu.get(n.f0.tokenImage) : new TypeInstance(null, TypeEnum.ERROR);
+            new TypeInstance(argu.get(n.f0.tokenImage).get_name(),
+                             argu.get(n.f0.tokenImage).get_type()) :
+            new TypeInstance(null, TypeEnum.ERROR);
 
         this.printNode(n, argu, false, ret.get_type());
         --this.offset;
@@ -968,7 +972,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      *
      * f0 -> "this"
      */
-    public TypeInstance visit(ThisExpression n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(ThisExpression n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -989,7 +993,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f3 -> Expression()
      * f4 -> "]"
      */
-    public TypeInstance visit(ArrayAllocationExpression n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(ArrayAllocationExpression n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -998,7 +1002,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
         n.f2.accept(this, argu);
         TypeInstance ret = n.f3.accept(this, argu);
         n.f4.accept(this, argu);
-        ret = (ret.get_type() == TypeEnum.integer) ? new TypeInstance(null, TypeEnum.int_array) :
+        ret = (ret.get_type() == TypeEnum.integer) ? new TypeInstance(null, TypeEnum.intarray) :
             new TypeInstance(null, TypeEnum.ERROR);
 
         this.printNode(n, argu, false, ret.get_type());
@@ -1015,7 +1019,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f2 -> "("
      * f3 -> ")"
      */
-    public TypeInstance visit(AllocationExpression n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(AllocationExpression n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -1035,7 +1039,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f0 -> "!"
      * f1 -> Expression()
      */
-    public TypeInstance visit(NotExpression n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(NotExpression n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
@@ -1054,7 +1058,7 @@ public class TypeCheckSimp implements GJVisitor<TypeInstance,HashMap<String,Type
      * f1 -> Expression()
      * f2 -> ")"
      */
-    public TypeInstance visit(BracketExpression n, HashMap<String,TypeInstance> argu) {
+    public TypeInstance visit(BracketExpression n, HashMap<String,AbstractInstance> argu) {
         ++this.offset;
         this.printNode(n, argu, true, null);
 
diff --git a/typecheck/library/TypeEnum.java b/typecheck/library/TypeEnum.java
deleted file mode 100644
index be6cab2..0000000
--- a/typecheck/library/TypeEnum.java
+++ /dev/null
@@ -1,5 +0,0 @@
-package typecheck.library;
-
-public enum TypeEnum {
-    classname, int_array, bool, integer, CHECK, ERROR
-}
diff --git a/typecheck/library/TypeInstance.java b/typecheck/library/TypeInstance.java
deleted file mode 100644
index 756d39b..0000000
--- a/typecheck/library/TypeInstance.java
+++ /dev/null
@@ -1,43 +0,0 @@
-package typecheck.library;
-
-public class TypeInstance {
-    TypeEnum type;
-    String type_name;
-
-    public String toString() {
-        return "name:" + type_name + "|type:" + type;
-    }
-
-    public TypeInstance(String type_name, TypeEnum type) {
-        this.type = type;
-        this.type_name = type_name;
-    }
-
-    public boolean equal_type(TypeInstance other) {
-        /**
-         * Given a TypeInstance object other,
-         * returns true if other object
-         * is the same type as this one.
-         *
-         * We can say two types are equal, as
-         * long as they are not equal on a
-         * type error!
-         */
-
-        return this.type != TypeEnum.ERROR &&
-            this.type == other.type;
-    }
-
-    public boolean has_checked() {
-        return type != TypeEnum.ERROR;
-    }
-
-    public TypeEnum get_type() {
-        return this.type;
-    }
-
-    public String get_type_name() {
-        return this.type_name;
-    }
-
-}
diff --git a/typecheck/library/Utilities.java b/typecheck/library/Utilities.java
deleted file mode 100644
index fad1e7e..0000000
--- a/typecheck/library/Utilities.java
+++ /dev/null
@@ -1,14 +0,0 @@
-package typecheck.library;
-
-public class Utilities {
-
-    public static void print_filter(String message, boolean newline) {
-        boolean debug = false;
-        if (debug) {
-            System.out.print(message);
-            if (newline)
-                System.out.println();
-        }
-    }
-
-}
diff --git a/typecheck/tests/RetrieveInteger.java b/typecheck/tests/RetrieveInteger.java
index 036ad8b..1997e38 100644
--- a/typecheck/tests/RetrieveInteger.java
+++ b/typecheck/tests/RetrieveInteger.java
@@ -4,7 +4,7 @@ class RetrieveInteger{
         int j ;
 
         i = new GetInteger() ;
-        j = i.GetInteger() ;
+        j = i.Get() ;
 
         System.out.println(j) ;
     }
diff --git a/vaporize/library/VaporizeSimp.java b/vaporize/library/VaporizeSimp.java
index 289ca25..80db36b 100644
--- a/vaporize/library/VaporizeSimp.java
+++ b/vaporize/library/VaporizeSimp.java
@@ -4,10 +4,6 @@ import syntaxtree.*;
 import visitor.*;
 import java.util.*;
 
-/**
- * Provides default methods which visit each node in the tree in depth-first
- * order.  Your visitors may extend this class.
- */
 public class VaporizeSimp<R,A> extends GJDepthFirst<R,A> {
 
     private int offset;