'Return True if this snippet could match the (partial) \'before\'.'

def could_match(self, before):

    self._matched = ''
    if (before and (before[(-1)] in ('    ', ' DCTB '))):
        before = ''
    if (before and (before.rstrip() is not before)):
        return False
    words = _words_for_line(self._trigger, before)
    if ('r' in self._opts):
        match = self._re_match(before)
    elif ('w' in self._opts):
        qwords = escape(words, '\\"')
        words_suffix = _vim.eval(('substitute("%s",    "\\\\v^.+<(.+)",    "\\\\1",    "")' % qwords))
        match = self._trigger.startswith(words_suffix)
        self._matched = words_suffix
        if (words_suffix != words):
            match = False
    elif ('i' in self._opts):
        match = self._trigger.startswith(words)
    else:
        match = self._trigger.startswith(words)
    if (match and (not self._matched)):
        self._matched = words
    if (('b' in self._opts) and match):
        text_before = before.rstrip()[:(- len(self._matched))]
        if (text_before.strip('     DCTB ') != ''):
            self._matched = ''
            return False
    return match
