lexer-applicative

Simple lexer based on applicative regular expressions

https://github.com/feuerbach/lexer-applicative

Version on this page:2.1
LTS Haskell 24.24:2.1.0.2
Stackage Nightly 2025-12-21:2.1.0.2
Latest on Hackage:2.1.0.2

See all snapshots lexer-applicative appears in

MIT licensed and maintained by Roman Cheplyaka
This version can be pinned in stack with:lexer-applicative-2.1@sha256:2ad68240f449e891edf92df33b7a7ebc7c54a8e4a96bb4d25fdeaded4090cd5f,1423

Module documentation for 2.1

Simple applicative lexer based on the article Lexical analysis with parser combinators and the regex-applicative library.

Changes

Changelog

2.1

  • Restore compatibility with older GHCs
  • Change the type of longestShortest

2.0

This is a major redesign of the API. Notable changes:

  • The lexer now supports parsing the longest prefix/shortest suffix (see longestShortest)
  • Instead of throwing an exception, we return a stream. The stream can be consumed directly, converted to a list or either-error-list of tokens.

1.1.1

Add tokensEither

1.1

Upgrade to srcloc 0.5

1.0.0.1

Signal a lexical error (instead of looping) when a regex does not consume any characters