Param used to have only mutable flag. Borrow is a subset of mutable. All old

code that used to set mutable to true will issue a warning without this fix, because you can not have mutable True and borrow False (default value). Getting that warning when you only set mutable but not borrow seems very annoying and unneccessary.

Param used to have only mutable flag. Borrow is a subset of mutable. All old
0787e40b · Razvan Pascanu · ef73f0fc · 0787e40b
--- a/theano/compile/pfunc.py
+++ b/theano/compile/pfunc.py
@@ -276,6 +276,11 @@ class Param(object):
        self.default = default
        self.name = name
        self.mutable = mutable
+        # Mutable implies borrow. You can get borrow = False because of the
+        # default and it is a bit annoying to require the user to set both
+        # borrow and mutable to True
+        if mutable:
+            borrow = True
        self.strict = strict
        self.allow_downcast = allow_downcast
        self.implicit = implicit