ENH: memoize.skipUnchanged has an invalidate "method"

fsl/utils/memoize.py

@@ -205,6 +205,18 @@ def skipUnchanged(func):
     *not* called. If the given value is different from the cached value (or
     there is no value), the decorated function is called.
 
+
+    The ``invalidate`` method may be called on a ``skipUnchanged``-decorated
+    function to clear the internal cache. For example::
+
+        @skipUnchanged
+        def setval(name, value):
+            # ...
+
+        # ...
+
+        setval.invalidate()
+
     .. note:: This decorator ignores the return value of the decorated
               function.
 
@@ -216,6 +228,10 @@ def skipUnchanged(func):
 
     cache = {}
 
+    # TODO merge skipUnchanged and Memoize somehow
+    def invalidate():
+        cache.clear()
+
     def wrapper(name, value, *args, **kwargs):
 
         oldVal = cache.get(name, None)
@@ -243,6 +259,8 @@ def skipUnchanged(func):
 
         return True
 
+    wrapper.invalidate = invalidate
+
     return wrapper