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Changes between Version 1 and Version 2 of Ticket #911

-              v1
+              v2
 {{{
 register.tag('name', func)
 register.filter('name', func, False)
+register.filter('name', func) # No has_arg, see below
 }}}
 In tags, resolve_variable_with_filters is gone.
 …
 }}}
 for those.
+Filters can now have default arguments, and whether they have an argument is inferred from the signature. So any
+Will upload patch after updating to take account of new-admin merge.
+{{{
+def filter_func(obj, _):
+}}}
+should be changed to
+{{{
+def filter_func(obj):
+}}}
+and the has_arg function is no longer accepted or useful.
+Filter arguments can be also now be variables which are resolved in the context as well as constant strings.