data-reify

Reify a recursive data structure into an explicit graph.

http://ku-fpg.github.io/software/data-reify/

LTS Haskell 23.23:0.6.4
Stackage Nightly 2025-05-22:0.6.4
Latest on Hackage:0.6.4

See all snapshots data-reify appears in

BSD-3-Clause licensed by Andy Gill
Maintained by Andy Gill
This version can be pinned in stack with:data-reify-0.6.4@sha256:5c683905b8dd2aaa2e712926a9af7a1e670e9d74f1fd1cc3d78050b3c610aeb7,4872

Module documentation for 0.6.4

Used by 4 packages in lts-22.44(full list with versions):
ad, copilot-language, data-reify, folds

data-reify Hackage version Build Status

data-reify provided the ability to turn recursive structures into explicit graphs. Many (implicitly or explicitly) recursive data structure can be given this ability, via a type class instance. This gives an alternative to using Ref for observable sharing.

Observable sharing in general is unsafe, so we use the IO monad to bound this effect, but can be used safely even with unsafePerformIO if some simple conditions are met. Typically this package will be used to tie the knot with DSLs that depend of observable sharing, like Lava.

Providing an instance for MuRef is the mechanism for allowing a structure to be reified into a graph, and several examples of this are provided.

History: Version 0.1 used unsafe pointer compares. Version 0.2 of data-reify used StableNames, and was much faster. Version 0.3 provided two versions of MuRef, the mono-typed version, for trees of a single type, and the dynamic-typed version, for trees of different types. Version 0.4 used Int as a synonym for Unique rather than Data.Unique for node ids, by popular demand. Version 0.5 merged the mono-typed and dynamic version again, by using DynStableName, an unphantomized version of StableName.

Changes

0.6.4 [2024.10.27]

  • Drop support for pre-8.0 versions of GHC.

0.6.3 [2020.10.12]

  • Fix a bug introduced in data-reify-0.6.2 where reifyGraph could return Graphs with duplicate key-value pairs.

0.6.2 [2020.09.30]

  • Use HashMaps and IntSets internally for slightly better performance.

0.6.1

  • Fix warnings in GHC 7.10.

0.5

  • Merge the mono-typed and dynamic version again, by using ‘DynStableName’, an unphantomized version of StableName.

0.4

  • Use ‘Int’ as a synonym for ‘Unique’ rather than ‘Data.Unique’ for node ids, by popular demand.

0.3

  • Provide two versions of ‘MuRef’, the mono-typed version, for trees of a single type, and the dynamic-typed version, for trees of different types.

0.2

  • Use ‘StableName’s, making data-reify much faster.

0.1

  • Use unsafe pointer compares.