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libfsm and friends: NFA, DFA, regular expressions and lexical analysis

; re -cb -pl dot '[Ll]ibf+(sm)*' '[Ll]ibre' | dot


Getting started:

Lexing is the process of categorising a stream of items by their spellings. The output from this process is a stream of tokens, each of a specific lexeme category, which are most commonly input to a parser responsible for asserting the order of these tokens is valid.

lx is an attempt to produce a simple, expressive, and unobtrusive lexer generator which is good at lexing, does just lexing, is language independent, and has no other features.

You get:

  • libfsm — library for manipulating FSM (NFA and DFA)
  • libre — library for compiling regular expressions to NFA
  • fsm(1) — command line interface for FSM
  • re(1) — command line interface for executing regular expressions
  • lx(1) — lexer generator

Clone with submodules (contains required .mk files):

; git clone --recursive

To build and install:

; pmake -r install

You can override a few things:

; CC=clang PREFIX=$HOME pmake -r install

Building depends on:

  • Any BSD make. This includes OpenBSD, FreeBSD and NetBSD make(1) and sjg's portable bmake (also packaged as pmake).

  • A C compiler. Any should do, but GCC and clang are best supported.

  • ar, ld, and a bunch of other stuff you probably already have.

Fuzzing depends on the theft property-based testing library:

Ideas, comments or bugs: