Checkers are functions that receive a grammar specification and any kind of data, and return True or False

checker -> grammar_spec -> data -> bool

In a more pythonic way:

class Checker:

     def __init__(self, grammarspec):

          self.grammarspec = grammarspec

     def check (self, data):


          return True

right now there are implementations available for regular expressions and BNF grammars. This function/class belongs to the grammar tools family:

  • Checker
  • Lexer
  • Parser

that are the most basic functions for grammars.