I noticed the bug in Pyramid where a match_param argument to view_config
would not allow dicts due to them being unhashable
(https://github.com/Pylons/pyramid/issues/425). This fix is to no longer
accept dicts as a parameter.

Would it be an acceptable idea to allow a two dimensional tuple (('param',
'value'), ('paramtwo', 'value2')). It seems inconvenient that to work with
the match_param I have to parse strings and format them to the format
specification instead of using some kind of mapping.

My use case might be kind of strange, but I still think using string format
for meaningful data instead of a mapping is weirder. My use case is to
extend the view_config class in the following manner to automate adding a
dynamic match_param argument:

from pyramid.view import view_config
class action_config(view_config):
    def __call__(self, wrapper):
        settings = self.__dict__
        # if no name is given use the name of the function to match
        # against the 'action' matchdict parameter
        name = settings.get('name', wrapper.__name__)
        # add custom predicate to view config
        try:
            settings.setdefault('match_param', {})['action'] = name
        except TypeError:
            raise Exception('match_param must be a dict')
        return view_config.__call__(self, wrapper)

--
Jason