- can now use most names from __builtins__ as variable names without explicit declaration (i.e. 'id', 'exception', 'range', etc.) [ticket:83]

diff --git a/CHANGES b/CHANGES
index 7e5c11c..7036ee9 100644
--- a/CHANGES
+++ b/CHANGES

@@ -48,7 +48,10 @@
     caller_stack._push_frame(), caller_stack._pop_frame().
 
 - Bugfixes:
-
+  - can now use most names from __builtins__ as variable
+    names without explicit declaration (i.e. 'id', 
+    'exception', 'range', etc.) [ticket:83]
+    
   - fixed bug in python generation when variable names are
     used with identifiers like "else", "finally", etc.
     inside them [ticket:68]

diff --git a/lib/mako/pyparser.py b/lib/mako/pyparser.py
index 372222f..df21a9b 100644
--- a/lib/mako/pyparser.py
+++ b/lib/mako/pyparser.py

@@ -9,11 +9,14 @@
 Parsing to AST is done via _ast on Python > 2.5, otherwise the compiler
 module is used.
 """
-import __builtin__
+
 import sys
 from StringIO import StringIO
 from mako import exceptions, util
 
+# words that cannot be assigned to (notably smaller than the total keys in __builtins__)
+reserved = set(['True', 'False', 'None'])
+
 new_ast = sys.version_info > (2, 5)
 
 if new_ast:
@@ -89,7 +92,7 @@
         def visit_Name(self, node):
             if isinstance(node.ctx, _ast.Store):
                 self._add_declared(node.id)
-            if not hasattr(__builtin__, node.id) and node.id not in self.listener.declared_identifiers and node.id not in self.local_ident_stack:
+            if node.id not in reserved and node.id not in self.listener.declared_identifiers and node.id not in self.local_ident_stack:
                 self.listener.undeclared_identifiers.add(node.id)
         def visit_Import(self, node):
             for name in node.names:
@@ -187,7 +190,7 @@
             self.visit(node.assign, *args)
             self.visit(node.body, *args)
         def visitName(self, node, *args):
-            if not hasattr(__builtin__, node.name) and node.name not in self.listener.declared_identifiers and node.name not in self.local_ident_stack:
+            if node.name not in reserved and node.name not in self.listener.declared_identifiers and node.name not in self.local_ident_stack:
                 self.listener.undeclared_identifiers.add(node.name)
         def visitImport(self, node, *args):
             for (mod, alias) in node.names:

diff --git a/lib/mako/runtime.py b/lib/mako/runtime.py
index 7704a95..b181287 100644
--- a/lib/mako/runtime.py
+++ b/lib/mako/runtime.py

@@ -8,21 +8,23 @@
 
 from mako import exceptions, util
 import inspect, sys
+import __builtin__
 
 class Context(object):
     """provides runtime namespace, output buffer, and various callstacks for templates."""
     def __init__(self, buffer, **data):
         self._buffer_stack = [buffer]
-        self._data = data
+        self._data = dict(__builtin__.__dict__)
+        self._data.update(data)
         self._kwargs = data.copy()
         self._with_template = None
         self.namespaces = {}
         
         # "capture" function which proxies to the generic "capture" function
-        data['capture'] = lambda x, *args, **kwargs: capture(self, x, *args, **kwargs)
+        self._data['capture'] = lambda x, *args, **kwargs: capture(self, x, *args, **kwargs)
         
         # "caller" stack used by def calls with content
-        self.caller_stack = data['caller'] = CallerStack()
+        self.caller_stack = self._data['caller'] = CallerStack()
         
     lookup = property(lambda self:self._with_template.lookup)
     kwargs = property(lambda self:self._kwargs.copy())

diff --git a/test/ast.py b/test/ast.py
index 8f348e5..f60be65 100644
--- a/test/ast.py
+++ b/test/ast.py

@@ -56,7 +56,7 @@
 (q for q in range (1, q))
 """
         parsed = ast.PythonCode(code, **exception_kwargs)
-        assert parsed.undeclared_identifiers == util.Set(['x', 'y', 'z', 'q'])
+        assert parsed.undeclared_identifiers == util.Set(['x', 'y', 'z', 'q', 'range'])
     
     def test_locate_identifiers_4(self):
         code = """

diff --git a/test/template.py b/test/template.py
index 123bfdf..634a9a3 100644
--- a/test/template.py
+++ b/test/template.py

@@ -215,6 +215,13 @@
         """)
         
         assert flatten_result(template.render(id="im the id")) == "this is page, id is im the id"
+    
+    def test_canuse_builtin_names(self):
+        template = Template("""
+            exception: ${exception}
+            id: ${id}
+        """)
+        assert flatten_result(template.render(id='some id', exception='some exception')) == "exception: some exception id: some id"
         
 class IncludeTest(unittest.TestCase):
     def test_basic(self):