parameters: (self, pattern)
return_statement: return self._re_cache[pattern].match(self.data, self.pos)
docstring: Apply `pattern` on the current position and return
          the match object. (Doesn't touch pos). Use this for
          lookahead.
docstring_summary: Apply `pattern` on the current position and return
          the match object. (Doesn't touch pos). Use this for
          lookahead.
docstring_tokens: Apply pattern on the current position and return the match object . ( Doesn t touch pos ) . Use this for lookahead .
function: def check(self, pattern):
          """
          Apply `pattern` on the current position and return
          the match object. (Doesn't touch pos). Use this for
          lookahead.
          """
          if self.eos:
              raise EndOfText()
          if pattern not in self._re_cache:
              self._re_cache[pattern] = re.compile(pattern, self.flags)
          return self._re_cache[pattern].match(self.data, self.pos)
function_tokens: def check ( self , pattern ) : if self . eos : raise EndOfText ( ) if pattern not in self . _re_cache : self . _re_cache [ pattern ] = re . compile ( pattern , self . flags ) return self . _re_cache [ pattern ] . match ( self . data , self . pos )