diff -Nru jython/org/python/compiler/CodeCompiler.java jython_diff/org/python/compiler/CodeCompiler.java
--- jython/org/python/compiler/CodeCompiler.java	2005-10-21 14:18:00.000000000 -0700
+++ jython_diff/org/python/compiler/CodeCompiler.java	2006-03-05 19:48:04.235443200 -0800
@@ -45,6 +45,7 @@
 import org.python.parser.ast.Lambda;
 import org.python.parser.ast.List;
 import org.python.parser.ast.ListComp;
+import org.python.parser.ast.GenExpr;
 import org.python.parser.ast.Name;
 import org.python.parser.ast.Num;
 import org.python.parser.ast.Pass;
@@ -68,6 +69,7 @@
 import org.python.parser.ast.expr_contextType;
 import org.python.parser.ast.keywordType;
 import org.python.parser.ast.listcompType;
+import org.python.parser.ast.genexprType;
 import org.python.parser.ast.modType;
 import org.python.parser.ast.stmtType;
 
@@ -2022,6 +2024,78 @@
         return null;
     }
 
+    public Object visitGenExpr(GenExpr node) throws Exception {
+    	String name="<genexpr>";
+        setline(node);
+
+        code.new_(code.pool.Class("org/python/core/PyFunction"));
+        code.dup();
+        loadFrame();
+        if (mrefs.f_globals == 0) {
+            mrefs.f_globals = code.pool.Fieldref(
+                "org/python/core/PyFrame", "f_globals", $pyObj);
+        }
+        code.getfield(mrefs.f_globals);
+
+        ScopeInfo scope = module.getScopeInfo(node);
+
+        makeArray(scope.ac.getDefaults());
+
+        scope.setup_closure(my_scope);
+        scope.dump();
+
+        stmtType stmts[]=new stmtType[1];
+        stmtType n = new Yield(node.target , node);
+
+        for (int i = node.generators.length - 1; i >= 0; i--) {
+        	genexprType ge = node.generators[i];
+        	for (int j = ge.ifs.length - 1; j >= 0; j--) {
+        			n = new If(ge.ifs[j], new stmtType[] { n }, null, ge.ifs[j]);
+        	}
+        	if (i==0) 
+				n = new For(ge.target, new Name("<outmost iterable>",Name.Load),
+												new stmtType[] { n }, null, ge);
+			else
+				n = new For(ge.target, ge.iter, new stmtType[] { n }, null, ge);
+        }
+        stmts[0]=n;
+        
+        module.PyCode(new Suite(stmts, node), name, true,
+                className, false, false,
+                node.beginLine, scope, cflags).get(code);
+        
+        Vector freenames = scope.freevars;
+        
+        getDocString(stmts);
+
+        if (!makeClosure(freenames)) {
+            if (mrefs.PyFunction_init == 0) {
+                mrefs.PyFunction_init = code.pool.Methodref(
+                    "org/python/core/PyFunction", "<init>",
+                    "(" + $pyObj + $pyObjArr + $pyCode + $pyObj + ")V");
+            }
+            code.invokespecial(mrefs.PyFunction_init);
+        } else {
+            if (mrefs.PyFunction_closure_init == 0) {
+                mrefs.PyFunction_closure_init = code.pool.Methodref(
+                    "org/python/core/PyFunction", "<init>",
+                    "(" + $pyObj + $pyObjArr + $pyCode + $pyObj + $pyObjArr +
+                    ")V");
+            }
+            code.invokespecial(mrefs.PyFunction_closure_init);
+        }
+        
+        if (mrefs.calla1 == 0) {
+            mrefs.calla1 = code.pool.Methodref(
+                "org/python/core/PyObject", "__call__",
+                "(" + $pyObj + ")" + $pyObj);
+        }
+        visit(node.generators[0].iter); // visit precomputed iterable
+        code.invokevirtual(mrefs.calla1);
+        
+        return null;	
+    }
+
     public Object visitDict(Dict node) throws Exception {
         code.new_(code.pool.Class("org/python/core/PyDictionary"));
         code.dup();
diff -Nru jython/org/python/compiler/ScopesCompiler.java jython_diff/org/python/compiler/ScopesCompiler.java
--- jython/org/python/compiler/ScopesCompiler.java	2002-10-15 07:32:28.000000000 -0700
+++ jython_diff/org/python/compiler/ScopesCompiler.java	2006-03-05 20:00:35.365515200 -0800
@@ -4,6 +4,7 @@
 
 import org.python.parser.*;
 import org.python.parser.ast.*;
+
 import java.util.*;
 
 public class ScopesCompiler extends Visitor implements ScopeConstants {
@@ -11,37 +12,36 @@
     private CompilationContext code_compiler;
 
     private Stack scopes;
+
     private ScopeInfo cur = null;
+
     private Hashtable nodeScopes;
 
     private int level      = 0;
     private int func_level = 0;
 
-    public ScopesCompiler(CompilationContext code_compiler,
-                          Hashtable nodeScopes)
-    {
+    public ScopesCompiler(CompilationContext code_compiler, Hashtable nodeScopes) {
         this.code_compiler = code_compiler;
         this.nodeScopes = nodeScopes;
         scopes = new Stack();
     }
 
     public void beginScope(String name, int kind, SimpleNode node,
-                           ArgListCompiler ac)
-    {
+                           ArgListCompiler ac) {
         if (cur != null) {
             scopes.push(cur);
         }
-        if (kind == FUNCSCOPE) func_level++;
-        cur = new ScopeInfo(name, node, level++, kind,
-                                         func_level, ac);
+        if (kind == FUNCSCOPE)
+            func_level++;
+        cur = new ScopeInfo(name, node, level++, kind, func_level, ac);
         nodeScopes.put(node, cur);
     }
 
     public void endScope() throws Exception {
         if (cur.kind == FUNCSCOPE) func_level--;
         level--;
-        ScopeInfo up = (!scopes.empty())?(ScopeInfo)scopes.pop():null;
-        cur.cook(up,code_compiler);
+        ScopeInfo up = (!scopes.empty()) ? (ScopeInfo) scopes.pop() : null;
+        cur.cook(up, code_compiler);
         cur.dump(); // dbg
         cur = up;
     }
@@ -49,7 +49,7 @@
     public void parse(SimpleNode node) throws Exception {
         try {
             visit(node);
-        } catch(Throwable t) {
+        } catch (Throwable t) {
             throw org.python.core.parser.fixParseError(null, t,
                     code_compiler.getFilename());
         }
@@ -63,8 +63,7 @@
     }
 
     public Object visitModule(org.python.parser.ast.Module node)
-        throws Exception
-    {
+            throws Exception {
         beginScope("<file-top>", TOPSCOPE, node, null);
         suite(node.body);
         endScope();
@@ -120,7 +119,7 @@
         beginScope("<lambda>", FUNCSCOPE, node, ac);
         int n = ac.names.size();
         for (int i = 0; i < n; i++) {
-            cur.addParam((String)ac.names.elementAt(i));
+            cur.addParam((String) ac.names.elementAt(i));
         }
         for (int i = 0; i < ac.init_code.size(); i++) 
             visit((stmtType) ac.init_code.elementAt(i));
@@ -173,14 +172,14 @@
             String name = node.names[i];
             int prev = cur.addGlobal(name);
             if (prev >= 0) {
-                if ((prev&FROM_PARAM) != 0)
-                    code_compiler.error("name '"+name+"' is local and global",
-                                        true,node);
-                if ((prev&GLOBAL) != 0) continue;
+                if ((prev & FROM_PARAM) != 0)
+                    code_compiler.error("name '" + name + "' is local and global",
+                                        true, node);
+                if ((prev & GLOBAL) != 0) continue;
                 String what;
-                if ((prev&BOUND) != 0) what = "assignment"; else what = "use";
-                code_compiler.error("name '"+name+"' declared global after "+
-                                    what,false,node);
+                if ((prev & BOUND) != 0) what = "assignment"; else what = "use";
+                code_compiler.error("name '" + name + "' declared global after "+
+                                    what, false, node);
             }
         }
         return null;
@@ -235,6 +234,56 @@
         return null;
     }
 
+    public Object visitGenExpr(GenExpr node) throws Exception {
+        String name = "GenExpr";// "<generator expressions>";
+        def(name);
+
+        // XXX FIXME: JIWON: need to capture first argument!
+        ArgListCompiler ac = new ArgListCompiler();
+
+        // added for pre-computation
+        exprType fpargs[]=new exprType[1];
+        fpargs[0] = new Name("<outmost iterable>",Name.Store);
+        argumentsType args=new argumentsType(fpargs, null, null, new exprType[0]);
+        ac.visitArgs(args);
+        // ac.visitName(node.target);
+        // ac.visitArgs(node.args);
+
+        // exprType[] defaults = ac.getDefaults();
+        // int defc = defaults.length;
+        // for (int i = 0; i < defc; i++) {
+        // visit(defaults[i]);
+        // }
+
+        beginScope(name, FUNCSCOPE, node, ac);
+        int size = ac.names.size();
+        for (int i = 0; i < size; i++) {
+            cur.addParam((String) ac.names.elementAt(i));
+        }
+        for (int i = 0; i < ac.init_code.size(); i++) {
+            visit((stmtType) ac.init_code.elementAt(i));
+        }
+        cur.markFromParam();
+
+        stmtType n = new Yield(node.target, node);
+
+        for (int i = node.generators.length - 1; i >= 0; i--) {
+            genexprType ge = node.generators[i];
+            for (int j = ge.ifs.length - 1; j >= 0; j--) {
+                n = new If(ge.ifs[j], new stmtType[] { n }, null, ge.ifs[j]);
+            }
+            if (i==0) 
+                n = new For(ge.target, new Name("<outmost iterable>",Name.Load),
+                                                new stmtType[] { n }, null, ge);
+            else
+                n = new For(ge.target, ge.iter, new stmtType[] { n }, null, ge);
+        }
+
+        suite(new stmtType[] { n });
+
+        endScope();
+        return null;
+    }
 
     public Object visitYield(Yield node) throws Exception {
         cur.generator = true;
diff -Nru jython/org/python/parser/TreeBuilder.java jython_diff/org/python/parser/TreeBuilder.java
--- jython/org/python/parser/TreeBuilder.java	2005-07-20 13:25:09.000000000 -0700
+++ jython_diff/org/python/parser/TreeBuilder.java	2006-03-05 20:16:07.515881600 -0800
@@ -1,5 +1,7 @@
 package org.python.parser;
 
+import java.util.EmptyStackException;
+
 import org.python.parser.ast.*;
 import org.python.core.PyObject;
 
@@ -39,7 +41,7 @@
     }
 
     private exprType makeExpr(SimpleNode node) {
-        return (exprType) node;
+    	return (exprType)node;
     }
 
     private exprType makeExpr() {
@@ -189,7 +191,7 @@
             String name = makeIdentifier();
             return new FunctionDef(name, arguments, body);
         case JJTDEFAULTARG:
-            value = (arity == 1) ? null : makeExpr();
+        	value = (arity == 1) ? null : makeExpr();
             return new DefaultArg(makeExpr(), value);
         case JJTEXTRAARGLIST:
             return new ExtraArg(makeIdentifier(), JJTEXTRAARGLIST);
@@ -261,7 +263,7 @@
             int[] ops = new int[l];
             for (int i = l-1; i >= 0; i--) {
                 comparators[i] = makeExpr();
-                SimpleNode op = (SimpleNode) stack.popNode();
+                SimpleNode op = (SimpleNode) stack.popNode();             
                 switch (op.getId()) {
                 case JJTLESS_CMP:          ops[i] = Compare.Lt; break;
                 case JJTGREATER_CMP:       ops[i] = Compare.Gt; break;
@@ -277,7 +279,8 @@
                     throw new RuntimeException("Unknown cmp op:" + op.getId());
                 }
             }
-            return new Compare(makeExpr(), ops, comparators);
+            return new Compare(makeExpr(), ops, comparators);    
+
         case JJTLESS_CMP:
         case JJTGREATER_CMP:
         case JJTEQUAL_CMP:
@@ -370,6 +373,14 @@
             name = makeIdentifier();
             return new keywordType(name, value);
         case JJTTUPLE:
+        	if (stack.nodeArity() > 0 && peekNode() instanceof genexprType) {
+        		System.out.println("JJTUPLE as genexpr");
+                genexprType[] generators = new genexprType[arity-1];
+                for (int i = arity-2; i >= 0; i--) {
+                    generators[i] = (genexprType) popNode();
+                }
+                return new GenExpr(makeExpr(), generators);
+            }
             return new Tuple(makeExprs(), Tuple.Load);
         case JJTLIST:
             if (stack.nodeArity() > 0 && peekNode() instanceof listcompType) {
@@ -459,6 +470,15 @@
             target = makeExpr();
             ctx.setStore(target);
             return new listcompType(target, iter, ifs);
+        case JJTGEN_FOR:
+            ifs = new exprType[arity-2];
+            for (int i = arity-3; i >= 0; i--) {
+                ifs[i] = makeExpr();
+            }
+            iter = makeExpr();
+            target = makeExpr();
+            ctx.setStore(target);
+            return new genexprType(target, iter, ifs);
         case JJTIMPORTFROM:
             aliasType[] aliases = makeAliases(arity - 1);
             String module = makeIdentifier();
@@ -549,7 +569,7 @@
         exprType[] newdefs = new exprType[l-startofdefaults];
         System.arraycopy(defaults, startofdefaults, newdefs, 0, newdefs.length);
         
-        return new argumentsType(fpargs, stararg, kwarg, newdefs);
+    return new argumentsType(fpargs, stararg, kwarg, newdefs);
     }
 }
 
diff -Nru jython/org/python/parser/ast/GenExpr.java jython_diff/org/python/parser/ast/GenExpr.java
--- jython/org/python/parser/ast/GenExpr.java	1969-12-31 16:00:00.000000000 -0800
+++ jython_diff/org/python/parser/ast/GenExpr.java	2006-02-21 12:56:07.755046400 -0800
@@ -0,0 +1,55 @@
+// Autogenerated AST node
+package org.python.parser.ast;
+import org.python.parser.SimpleNode;
+import java.io.DataOutputStream;
+import java.io.IOException;
+
+public class GenExpr extends SimpleNode {
+    public exprType target;
+    public genexprType[] generators;
+
+    public GenExpr(exprType target, genexprType[] generators) {
+        this.target = target;
+        this.generators = generators;
+    }
+
+    public GenExpr(exprType target, genexprType[] generators, SimpleNode
+    parent) {
+        this(target, generators);
+        this.beginLine = parent.beginLine;
+        this.beginColumn = parent.beginColumn;
+    }
+
+    public String toString() {
+        StringBuffer sb = new StringBuffer("GenExpr[");
+        sb.append("target=");
+        sb.append(dumpThis(this.target));
+        sb.append(", ");
+        sb.append("generators=");
+        sb.append(dumpThis(this.generators));
+        sb.append("]");
+        return sb.toString();
+    }
+
+    public void pickle(DataOutputStream ostream) throws IOException {
+        pickleThis(34, ostream);
+        pickleThis(this.target, ostream);
+        pickleThis(this.generators, ostream);
+    }
+
+    public Object accept(VisitorIF visitor) throws Exception {
+        return visitor.visitGenExpr(this);
+    }
+
+    public void traverse(VisitorIF visitor) throws Exception {
+        if (target != null)
+            target.accept(visitor);
+        if (generators != null) {
+            for (int i = 0; i < generators.length; i++) {
+                if (generators[i] != null)
+                    generators[i].accept(visitor);
+            }
+        }
+    }
+
+}
diff -Nru jython/org/python/parser/ast/VisitorBase.java jython_diff/org/python/parser/ast/VisitorBase.java
--- jython/org/python/parser/ast/VisitorBase.java	2005-07-20 13:25:09.000000000 -0700
+++ jython_diff/org/python/parser/ast/VisitorBase.java	2005-12-16 18:49:19.530555200 -0800
@@ -201,6 +201,12 @@
         return ret;
     }
 
+    public Object visitGenExpr(GenExpr node) throws Exception {
+        Object ret = unhandled_node(node);
+        traverse(node);
+        return ret;
+    }
+
     public Object visitCompare(Compare node) throws Exception {
         Object ret = unhandled_node(node);
         traverse(node);
diff -Nru jython/org/python/parser/ast/VisitorIF.java jython_diff/org/python/parser/ast/VisitorIF.java
--- jython/org/python/parser/ast/VisitorIF.java	2005-07-20 13:25:09.000000000 -0700
+++ jython_diff/org/python/parser/ast/VisitorIF.java	2005-12-16 18:31:54.177411200 -0800
@@ -35,12 +35,13 @@
     public Object visitLambda(Lambda node) throws Exception;
     public Object visitDict(Dict node) throws Exception;
     public Object visitListComp(ListComp node) throws Exception;
+    public Object visitGenExpr(GenExpr node) throws Exception;
     public Object visitCompare(Compare node) throws Exception;
     public Object visitCall(Call node) throws Exception;
     public Object visitRepr(Repr node) throws Exception;
     public Object visitNum(Num node) throws Exception;
     public Object visitStr(Str node) throws Exception;
-    public Object visitUnicode(Unicode node) throws Exception;
+    public Object visitUnicode(Unicode node) throws Exception;   
     public Object visitAttribute(Attribute node) throws Exception;
     public Object visitSubscript(Subscript node) throws Exception;
     public Object visitName(Name node) throws Exception;
diff -Nru jython/org/python/parser/ast/genexprType.java jython_diff/org/python/parser/ast/genexprType.java
--- jython/org/python/parser/ast/genexprType.java	1969-12-31 16:00:00.000000000 -0800
+++ jython_diff/org/python/parser/ast/genexprType.java	2006-02-21 12:52:03.734161600 -0800
@@ -0,0 +1,65 @@
+// Autogenerated AST node
+package org.python.parser.ast;
+import org.python.parser.SimpleNode;
+import java.io.DataOutputStream;
+import java.io.IOException;
+
+//public class genexprType extends SimpleNode {
+public class genexprType extends exprType {
+    public exprType target;
+    public exprType iter;
+    public exprType[] ifs;
+
+    public genexprType(exprType target, exprType iter, exprType[] ifs) {
+        this.target = target;
+        this.iter = iter;
+        this.ifs = ifs;
+    }
+
+    public genexprType(exprType target, exprType iter, exprType[] ifs,
+    SimpleNode parent) {
+        this(target, iter, ifs);
+        this.beginLine = parent.beginLine;
+        this.beginColumn = parent.beginColumn;
+    }
+
+    public String toString() {
+        StringBuffer sb = new StringBuffer("genexpr[");
+        sb.append("target=");
+        sb.append(dumpThis(this.target));
+        sb.append(", ");
+        sb.append("iter=");
+        sb.append(dumpThis(this.iter));
+        sb.append(", ");
+        sb.append("ifs=");
+        sb.append(dumpThis(this.ifs));
+        sb.append("]");
+        return sb.toString();
+    }
+
+    public void pickle(DataOutputStream ostream) throws IOException {
+        pickleThis(50, ostream);
+        pickleThis(this.target, ostream);
+        pickleThis(this.iter, ostream);
+        pickleThis(this.ifs, ostream);
+    }
+
+    public Object accept(VisitorIF visitor) throws Exception {
+        traverse(visitor);
+        return null;
+    }
+
+    public void traverse(VisitorIF visitor) throws Exception {
+        if (target != null)
+            target.accept(visitor);
+        if (iter != null)
+            iter.accept(visitor);
+        if (ifs != null) {
+            for (int i = 0; i < ifs.length; i++) {
+                if (ifs[i] != null)
+                    ifs[i].accept(visitor);
+            }
+        }
+    }
+
+}
diff -Nru jython/org/python/parser/python.jjt jython_diff/org/python/parser/python.jjt
--- jython/org/python/parser/python.jjt	2005-07-20 13:25:09.000000000 -0700
+++ jython_diff/org/python/parser/python.jjt	2006-02-26 15:03:59.137145600 -0800
@@ -1,5 +1,5 @@
 // -*- java -*-
-// Copyright © Corporation for National Research Initiatives
+// Copyright ? Corpforation for National Research Initiatives
 
 options
 {
@@ -914,7 +914,7 @@
 void atom() #void: {}
 {
     LOOKAHEAD(2) (  <LPAREN> <RPAREN> ) #tuple
-|   ( <LPAREN> [SmartTestList()] <RPAREN> )
+|   ( <LPAREN> [SmartTestListGexp()] <RPAREN> )
 |   ( <LBRACKET> [listmaker()] <RBRACKET> ) #list
 |   ( <LBRACE> [dictmaker()] <RBRACE> ) #dictionary
 |   "`" SmartTestList() "`" #str_1op(1)
@@ -923,7 +923,6 @@
 |   String() (String() #strjoin(2))*
 }
 
-
 //lambdef: 'lambda' [varargslist] ':' test
 void lambdef():{}
 { <LAMBDA> [varargslist()] <COLON> test() }
@@ -963,6 +962,10 @@
 void dictmaker() #void: {}
 {test() <COLON> test() (LOOKAHEAD(2) <COMMA> test() <COLON> test())* [<COMMA>]}
 
+//testlist_gexp: test (',' test)* [',']
+void SmartTestListGexp() #void: {}
+{ test() ( (gen_for())+ | (LOOKAHEAD(2) <COMMA> test())* [Comma()] ) #tuple(>1) }
+
 //listmaker: test ( list_for | (',' test)* [','] )
 void listmaker() #void: {}
 { test() ( (list_for())+ | (LOOKAHEAD(2) <COMMA> test())* [Comma()] #tuple(>1)) }
@@ -979,6 +982,13 @@
 void list_if() #void: {}
 { <IF> test() }
 
+//gen_for: 'for' exprlist 'in' testlist gen_iter
+void gen_for(): {}
+{ <FOR> exprlist() <IN> SmartTestList() (gen_if())* }
+
+//gen_if: 'if' test list_iter
+void gen_if() #void: {}
+{ <IF> test() }
 
 //classdef: 'class' NAME ['(' testlist ')'] ':' suite
 void classdef(): {}
@@ -1009,7 +1019,6 @@
 void argument() #void: {}
 { ([LOOKAHEAD(2) AnyName() <EQUAL>] test()) #Keyword(>1) }
 
-
 void Number() #Num :
 {
     Token t;