Added documentation on output_keys argument. Switched str to basestring

theano/compile/debugmode.py

@@ -2196,6 +2196,10 @@ class _Maker(FunctionMaker):  # inheritance buys a few helper functions
         :param on_unused_input: What to do if a variable in the 'inputs' list is
         not used in the graph. Possible values are 'raise', 'warn', and 'ignore'.
 
+        :param output_keys: If the outputs argument for theano.function was a
+        list, then output_keys is None.  If the outputs argument was a dict, 
+        then output_keys is a sorted list of the keys from that dict.  
+
         :note: this function sets TensorType.filter_checks_isfinite
         when `mode.check_isfinite` is True
 

theano/compile/function.py

@@ -49,7 +49,8 @@ def function(inputs, outputs=None, mode=None, updates=None, givens=None,
     :param inputs: function parameters, these are not allowed to be shared
     variables
 
-    :type outputs: list of Variables or Out instances
+    :type outputs: list or dict of Variables or Out instances.  If it is a 
+    dict, the keys must be strings
     :param outputs: expressions to compute
 
     :type mode: string or `Mode` instance.
@@ -193,7 +194,7 @@ def function(inputs, outputs=None, mode=None, updates=None, givens=None,
         output_keys = []
         outputs = []
         for pair in output_items_sorted: 
-            assert isinstance(pair[0], str)
+            assert isinstance(pair[0], basestring)
             output_keys.append(pair[0])
             outputs.append(pair[1])
 

theano/compile/function_module.py

@@ -1442,6 +1442,11 @@ def orig_function(inputs, outputs, mode=None, accept_inplace=False,
     :param on_unused_input: What to do if a variable in the 'inputs' list is
         not used in the graph. Possible values are 'raise', 'warn', 'ignore'
         and None
+
+    :param output_keys: If the outputs were provided to theano.function as a
+        list, then output_keys is None.  Otherwise, if outputs were provided
+        as a dict, output_keys is the sorted list of keys from the outputs
+
     """
 
     # Every element of the input list will be upgraded to an `In` instance if

theano/compile/pfunc.py

@@ -506,7 +506,7 @@ def pfunc(params, outputs=None, mode=None, updates=None, givens=None,
                     mutable=False, borrow=True, shared=True)
         inputs.append(si)
 
-    return orig_function(inputs, cloned_outputs, mode, 
+    return orig_function(inputs, cloned_outputs, mode,
             accept_inplace=accept_inplace, name=name, profile=profile,
             on_unused_input=on_unused_input, output_keys=output_keys)