aPTK - A Parse Toolkit

aPTK is a Parse Toolkit. It is useful to write documented grammars similar to BNF grammar language.

Typically you would use it like this:

from aptk import *

class AdditionGrammar(Grammar):
    '''This is the grammar of a simple addition.

    <addition> := <operand> <.ws> "+" <.ws> <operand>
    <ws>       := \s*
    <operand>  := \d+

class AdditionActions(ParseActions):
    def make_operand(self, p, lexem):
        return int(str(lexem))

    def make_addition(self, p, lexem):
        return lexem[0].ast + lexem[1].ast

tree = parse("5 + 4", AdditionGrammar)
result = ast("5 + 4", AdditionGrammar, AdditionActions)

The most interesting on the grammars derived from BaseGrammar is that they are compiled at compile-time of your python module. This is possible due to some python voodoo with metaclasses in grammar.

Indices and tables