linenoise

A lightweight readline-replacement library for Haskell based on the linenoise library. (Not production ready!) See the demo app for usage, or see the climb library for higher-level building blocks for GHCi-like REPLs with colon-commands.

Differences from alternatives

• haskeline
  • This uses FFI to a minimal C library vs pure Haskell
  • This uses standard MTL/Unlift typeclasses vs custom ones.
  • This does not require the use of a specific monad transformer.
• readline
  • This offers a MonadIO/MonadUnliftIO interface vs raw IO.
  • This vendors and statically links its underlying library to simplify the build process.

License and attribution

This library includes the source code and license for linenoise in cbits. It is a fork of an older library with all licensing and attribution preserved.

Development workflow

This project uses stack to build.

The Makefile has a bunch of relevant phony targets for a development workflow including

• build - Build the library and demo
• download - Update vendored linenoise
• demo - Run the demo app
• deps - Install dev tools
• lint - Lint with hlint
• format - Format with stylish-haskell
• docs - Generate docs

In addition, there are targets starting with ci that are invoked in various CI phases.

TODO

• Support unicode (may involve vendoring a linenoise fork)
• Verify that the FFI modifications for ByteString are memory-safe