Finds progress information in the text using the
        user-supplied regex and calculation instructions

def _extract_progress(self, text):
        '''
        Finds progress information in the text using the
        user-supplied regex and calculation instructions
        '''
        # monad-ish dispatch to avoid the if/else soup
        find = partial(re.search, string=text.strip().decode(self.encoding))
        regex = unit(self.progress_regex)
        match = bind(regex, find)
        result = bind(match, self._calculate_progress)
        return result