bnf

BNF Parser example

Introduction

This is an advanced demo that uses ParserKit to create a Yacc-like table-driven parser generator. The tool consumes an input file using Yacc syntax and outputs the code for an LL(1) table-driven parser. As with Yacc you can embed semantic actions in the grammar input file.

If you are not familiar with Yacc you may want to read about it before jumping into this example.

This example is very complicated. It is primarily intended to show more of the range of what can be done with the ParserKit library.

There are some significant challenges with LL(1) parsers and the order in which the parse tree is evaluated. This becomes obvious when parsing arithmetic expressions. In partciular, it is very difficult to define an LL(1) parser that follows normal operator precedence rules.