use threading.local if available

speed up ThreadLocal for python 2.3 [ticket:743]
clean in topo (in patch from [ticket:743])

1 files changed, 26 insertions, 20 deletions

diff --git a/lib/sqlalchemy/util.py b/lib/sqlalchemy/util.py
index 82815f101..37dfeb211 100644
--- a/lib/sqlalchemy/util.py
+++ b/lib/sqlalchemy/util.py
@@ -366,26 +366,32 @@ class OrderedDict(dict):
         self._list.remove(item[0])
         return item
 
-class ThreadLocal(object):
-    """An object in which attribute access occurs only within the context of the current thread."""
-
-    def __init__(self):
-        self.__dict__['_tdict'] = {}
-
-    def __delattr__(self, key):
-        try:
-            del self._tdict["%d_%s" % (thread.get_ident(), key)]
-        except KeyError:
-            raise AttributeError(key)
-
-    def __getattr__(self, key):
-        try:
-            return self._tdict["%d_%s" % (thread.get_ident(), key)]
-        except KeyError:
-            raise AttributeError(key)
-
-    def __setattr__(self, key, value):
-        self._tdict["%d_%s" % (thread.get_ident(), key)] = value
+try:
+    from threading import local as ThreadLocal
+except ImportError:
+    try:
+        from dummy_threading import local as ThreadLocal
+    except ImportError:
+        class ThreadLocal(object):
+            """An object in which attribute access occurs only within the context of the current thread."""
+
+            def __init__(self):
+                self.__dict__['_tdict'] = {}
+
+            def __delattr__(self, key):
+                try:
+                    del self._tdict[(thread.get_ident(), key)]
+                except KeyError:
+                    raise AttributeError(key)
+
+            def __getattr__(self, key):
+                try:
+                    return self._tdict[(thread.get_ident(), key)]
+                except KeyError:
+                    raise AttributeError(key)
+
+            def __setattr__(self, key, value):
+                self._tdict[(thread.get_ident(), key)] = value
 
 class DictDecorator(dict):
     """A Dictionary that delegates items not found to a second wrapped dictionary."""