'Add parse action to expression\'s list of parse actions. See L{I{setParseAction}<setParseAction>}.'

def addParseAction(self, *fns, **kwargs):

    self.parseAction += map(self._normalizeParseActionArgs, list(fns))
    self.callDuringTry = (self.callDuringTry or (('callDuringTry' in kwargs) and kwargs['callDuringTry']))
    return self
