Safe Haskell	None
Language	Haskell2010

MemDerive

Description

This module is an efficient implementation of the derivative algorithm for trees.

It is intended to be used for production purposes.

This means that it gives up some readability for speed.

This module provides memoization of the nullable, calls and returns functions.

Synopsis

Documentation

derive is the classic derivative implementation for trees.

Mem is the object used to store memoized results of the nullable, calls and returns functions.

newMem creates a object used for memoization by the validate function. Each grammar should create its own memoize object.

nullable returns whether a pattern is nullable and memoizes the results.

validate is the uses the derivative implementation for trees and return whether tree is valid, given the input grammar and start pattern.