Closes #1075: fix docs for @simplefilter.

The function needs a "self" argument since it is used as a method in the
automatically created class.  No use fixing that in the code, as it
kills backwards compatibility.

1 files changed, 3 insertions, 2 deletions

diff --git a/doc/docs/filterdevelopment.rst b/doc/docs/filterdevelopment.rst
index 5f9ca8c7..fbcd0a09 100644
--- a/doc/docs/filterdevelopment.rst
+++ b/doc/docs/filterdevelopment.rst
@@ -58,7 +58,7 @@ You can also use the `simplefilter` decorator from the `pygments.filter` module:
 
 
     @simplefilter
-    def uncolor(lexer, stream, options):
+    def uncolor(self, lexer, stream, options):
         class_too = get_bool_opt(options, 'classtoo')
         for ttype, value in stream:
             if ttype is Name.Function or (class_too and
@@ -67,4 +67,5 @@ You can also use the `simplefilter` decorator from the `pygments.filter` module:
             yield ttype, value
 
 The decorator automatically subclasses an internal filter class and uses the
-decorated function for filtering.
+decorated function as a method for filtering.  (That's why there is a `self`
+argument that you probably won't end up using in the method.)