ghc-exactprint

ExactPrint for GHC

Version on this page:0.5.6.1
LTS Haskell 24.28:1.10.0.0
Stackage Nightly 2026-01-15:1.12.0.0
Latest on Hackage:1.14.0.0

See all snapshots ghc-exactprint appears in

BSD-3-Clause licensed by Alan Zimmerman, Matthew Pickering
Maintained by [email protected]
This version can be pinned in stack with:ghc-exactprint-0.5.6.1@sha256:bfd45b82a5304e410b5dda53c6667fc082d5adf3d72480b83558033176fcc310,7331

Module documentation for 0.5.6.1

Using the API Annotations available from GHC 7.10.2, this library provides a means to round trip any code that can be compiled by GHC, currently excluding lhs files.

It does this with a phased approach

  • Delta - converts GHC API Annotations into relative offsets, indexed by SrcSpan

  • Transform - functions to facilitate changes to the AST, adjusting the annotations generated in the Delta phase to suit the changes.

  • Print - converts an AST and its annotations to properly formatted source text.

  • Pretty - adds annotations to an AST (fragment) so that the output can be parsed back to the same AST.

Note: requires GHC 7.10.2 or later