re-added clone to env

gof/env.py

@@ -408,6 +408,18 @@ class Env(utils.object2):
         return "[%s]" % ", ".join(graph.as_string(self.inputs, self.outputs))
 
 
+    ### clone ###
+
+    def clone(self):
+        return self.clone_get_equiv()[0]
+
+    def clone_get_equiv(self):
+        g, equiv = graph.clone_get_equiv(self.inputs, self.outputs)
+        e = Env([equiv[i] for i in self.inputs],
+                [equiv[o] for o in self.outputs])
+        for feature in self._features:
+            e.extend(feature)
+        return e, equiv
 
 
 

gof/link.py

@@ -268,8 +268,15 @@ class MetaLinker(Linker):
         pass
 
     def make_thunk(self, **kwargs):
+        """
+        You can pass an alternate env to use with the 'alt_env'
+        option.
 
-        env = self.env
+        The rest of the options will be passed to all the linkers
+        associated with this MetaLinker.
+        """
+
+        env = kwargs.pop("alt_env", self.env)
         no_recycling = self.no_recycling
 
         fns, input_lists, output_lists, thunk_lists, order_lists = zip(*[linker(env, no_recycling = no_recycling).make_all(**kwargs)