support for arglists with implicit tuple unpacks

- added a number of support methods to generate code just before the
  body
- hack protocol for communicating number of args to PyAssembler

fix TryExcept generation for case where exception handler has no body
fix visitAssAttr
add comment about incomplete visitAssName

stop using the ExampleASTVisitor

change script invocation to accept a list of .py files (e.g. Lib/*.py)

Lib/compiler/pycodegen.py

@@ -16,6 +16,7 @@
 import os
 import stat
 import struct
+import types
 
 def parse(path):
     f = open(path)
@@ -177,7 +178,10 @@ def emit(self, *args):
     def _generateFunctionOrLambdaCode(self, func):
         self.name = func.name
         self.filename = filename
-        args = func.argnames
+
+        # keep a lookout for 'def foo((x,y)):'
+        args, hasTupleArg = self.generateArglist(func.argnames)
+        
 	self.code = PyAssembler(args=args, name=func.name,
                                  filename=filename)
         self.namespace = self.OPTIMIZED
@@ -188,8 +192,41 @@ def _generateFunctionOrLambdaCode(self, func):
         lnf = walk(func.code, LocalNameFinder(args), 0)
         self.locals.push(lnf.getLocals())
 	self.emit('SET_LINENO', func.lineno)
+	if hasTupleArg:
+            self.generateArgUnpack(func.argnames)
         walk(func.code, self)
 
+    def generateArglist(self, arglist):
+        args = []
+        extra = []
+        count = 0
+        for elt in arglist:
+            if type(elt) == types.StringType:
+                args.append(elt)
+            elif type(elt) == types.TupleType:
+                args.append(".nested%d" % count)
+                count = count + 1
+                extra.extend(misc.flatten(elt))
+            else:
+                raise ValueError, "unexpect argument type:", elt
+        return args + extra, count
+
+    def generateArgUnpack(self, args):
+        count = 0
+        for arg in args:
+            if type(arg) == types.TupleType:
+                self.emit('LOAD_FAST', '.nested%d' % count)
+                count = count + 1
+                self.unpackTuple(arg)
+                        
+    def unpackTuple(self, tup):
+        self.emit('UNPACK_TUPLE', len(tup))
+        for elt in tup:
+            if type(elt) == types.TupleType:
+                self.unpackTuple(elt)
+            else:
+                self.emit('STORE_FAST', elt)
+
     def generateFunctionCode(self, func):
         """Generate code for a function body"""
         self._generateFunctionOrLambdaCode(func)
@@ -391,7 +428,8 @@ def visitWhile(self, node):
         else:
             lElse = l.breakAnchor
         l.startAnchor.bind(self.code.getCurInst())
-        self.emit('SET_LINENO', node.test.lineno)
+        if hasattr(node.test, 'lineno'):
+            self.emit('SET_LINENO', node.test.lineno)
         self.visit(node.test)
         self.emit('JUMP_IF_FALSE', lElse)
         self.emit('POP_TOP')
@@ -455,7 +493,8 @@ def visitTryExcept(self, node):
             self.emit('POP_TOP')
             self.visit(body)
             self.emit('JUMP_FORWARD', end)
-            next.bind(self.code.getCurInst())
+            if expr:
+                next.bind(self.code.getCurInst())
             self.emit('POP_TOP')
         self.emit('END_FINALLY')
         if node.else_:
@@ -553,7 +592,6 @@ def visitSubscript(self, node):
             self.emit('STORE_SUBSCR')
 	elif node.flags == 'OP_DELETE':
             self.emit('DELETE_SUBSCR')
-        print
         return 1
 
     def visitSlice(self, node):
@@ -596,16 +634,20 @@ def visitAssign(self, node):
         return 1
 
     def visitAssName(self, node):
+        # XXX handle OP_DELETE
         if node.flags != 'OP_ASSIGN':
             print "oops", node.flags
         self.storeName(node.name)
 
     def visitAssAttr(self, node):
-        if node.flags != 'OP_ASSIGN':
+        self.visit(node.expr)
+        if node.flags == 'OP_ASSIGN':
+            self.emit('STORE_ATTR', node.attrname)
+        elif node.flags == 'OP_DELETE':
+            self.emit('DELETE_ATTR', node.attrname)
+        else:
             print "warning: unexpected flags:", node.flags
             print node
-        self.visit(node.expr)
-        self.emit('STORE_ATTR', node.attrname)
         return 1
 
     def visitAssTuple(self, node):
@@ -865,7 +907,7 @@ def compile(self):
         t = transformer.Transformer()
         self.ast = t.parsesuite(self.source)
         cg = CodeGenerator(self.filename)
-        walk(self.ast, cg, walker=ExampleASTVisitor)
+        walk(self.ast, cg)
         self.code = cg.asConst()
 
     def dump(self, path):
@@ -888,18 +930,22 @@ def _pyc_header(self):
 if __name__ == "__main__":
     import getopt
 
+    VERBOSE = 0
     opts, args = getopt.getopt(sys.argv[1:], 'vq')
     for k, v in opts:
         if k == '-v':
+            VERBOSE = 1
             ASTVisitor.VERBOSE = ASTVisitor.VERBOSE + 1
         if k == '-q':
             f = open('/dev/null', 'wb')
             sys.stdout = f
-    if args:
-        filename = args[0]
+    if not args:
+        print "no files to compile"
     else:
-        filename = 'test.py'
-    buf = open(filename).read()
-    mod = CompiledModule(buf, filename)
-    mod.compile()
-    mod.dump(filename + 'c')
+        for filename in args:
+            if VERBOSE:
+                print filename
+            buf = open(filename).read()
+            mod = CompiledModule(buf, filename)
+            mod.compile()
+            mod.dump(filename + 'c')