Issues

• Strict prefix/lazy suffix for states?

  haskell/containers#1261 · Filter by author Zemyla opened on Sep 29, 2026
  9

• unfoldTree is too lazy

  major-releasestrictnessTree
  haskell/containers#1260 · Filter by author meooow25 opened on Sep 27, 2026

• IntSet's minView and maxView creates unwanted thunks

  IntSetlow-hanging-fruitperformance
  haskell/containers#1251 · Filter by author meooow25 opened on Sep 14, 2026

• Drop GHC 8.2/base-4.10 in next major release

  maintainabilitymajor-release
  haskell/containers#1250 · Filter by author meooow25 opened on Sep 4, 2026

• IntSet.difference: SpecConstr reboxing defeats the NOM -> t1 sharing at -O2

  haskell/containers#1242 · Filter by author sjakobi opened on Aug 21, 2026

• IntMap.delete allocates even for absent keys

  performance
  haskell/containers#1220 · Filter by author sjakobi opened on Jun 13, 2026
  3

• Add tryInsert for sets and maps

  feature-requestIntMapIntSetMapSet
  haskell/containers#1205 · Filter by author meooow25 opened on Apr 25, 2026
  7

• Add unzip and unzipWith for Map and IntMap

  feature-requestIntMapMap
  haskell/containers#1174 · Filter by author treeowl opened on Jan 4, 2026
  8

• Set.split and Set.splitMember should be strict in the key

  major-releaseSetstrictness
  haskell/containers#1171 · Filter by author meooow25 opened on Dec 28, 2025

• -> Solo a functions for lazy maps

  feature-requestIntMapMap
  haskell/containers#1132 · Filter by author meooow25 opened on Apr 13, 2025
  2

• Strict maps as newtypes

  discussion/rfcIntMapMap
  haskell/containers#1124 · Filter by author meooow25 opened on Mar 21, 2025
  13

• Get tests working with MicroHs

  testing
  haskell/containers#1120 · Filter by author meooow25 opened on Mar 2, 2025

• Consider moving the tutorial off Read the Docs

  discussion/rfcdocs
  haskell/containers#1100 · Filter by author meooow25 opened on Jan 26, 2025

• Improved representation for Set and Map

  discussion/rfcMapperformanceSet
  haskell/containers#1073 · Filter by author meooow25 opened on Nov 28, 2024
  3

• Faster IntMap.size and IntSet.size

  IntMapIntSetperformance
  haskell/containers#1062 · Filter by author meooow25 opened on Nov 2, 2024

• More efficient folds for Seq

  discussion/rfcperformanceSeq
  haskell/containers#1036 · Filter by author meooow25 opened on Sep 10, 2024
  6

• Add "Unsafe" modules

  discussion/rfcfeature-request
  haskell/containers#1026 · Filter by author treeowl opened on Aug 13, 2024
  6

• More accurate Set and Map size warnings

  docsMapSet
  haskell/containers#1010 · Filter by author meooow25 opened on Jun 8, 2024
  3

• Full IntSets?

  discussion/rfcIntSetperformance
  haskell/containers#999 · Filter by author meooow25 opened on Apr 6, 2024
  5

• Errors when trying to generate a test coverage report

  testing
  haskell/containers#997 · Filter by author meooow25 opened on Mar 29, 2024
  10

• Data.Graph: detect cycles utility functions

  feature-requestGraph
  haskell/containers#978 · Filter by author gwern opened on Dec 13, 2023
  2

• better instance Hashable IntSet?

  feature-requestIntSet
  haskell/containers#964 · Filter by author jwaldmann opened on Jul 17, 2023
  9

• Use generic map merging framework

  feature-requestIntMapMap
  haskell/containers#937 · Filter by author jcranch opened on Mar 13, 2023
  6

• Optimize scc as hard as possible

  Graphperformance
  haskell/containers#929 · Filter by author treeowl opened on Feb 2, 2023
  3

• Should dfs be lazy?

  Graphperformance
  haskell/containers#918 · Filter by author treeowl opened on Jan 30, 2023
  8