82 def matcher(cwd, pats, inc, exc, head = ''):

    83     def regex(name, tail):

    84         '''convert a pattern into a regular expression'''

    85         if name.startswith('re:'):

    86             return name[3:]

    87         elif name.startswith('path:'):

    88             return '^' + re.escape(name[5:]) + '$'

    89         elif name.startswith('glob:'):

    90             return head + globre(name[5:], '', tail)

    91         return head + globre(name, '', tail)

    92 

    93     def under(fn):

    94         """check if fn is under our cwd"""

    95         return not cwd or fn.startswith(cwdsep)

    96 

    97     def matchfn(pats, tail):

    98         """build a matching function from a set of patterns"""

    99         if pats:

   100             pat = '(?:%s)' % '|'.join([regex(p, tail) for p in pats])

   101             if cwd:

   102                 pat = re.escape(cwd + os.sep) + pat

   103             return re.compile(pat).match

   104 

   105     cwdsep = cwd + os.sep

   106     patmatch = matchfn(pats, '$') or (lambda fn: True)

   107     incmatch = matchfn(inc, '(?:/|$)') or under

   108     excmatch = matchfn(exc, '(?:/|$)') or (lambda fn: False)

   109 

   110     return lambda fn: (incmatch(fn) and not excmatch(fn) and

   111                        (fn.endswith('/') or patmatch(fn)))

   112