#13593: Unexpected behavior from Data.List.groupBy -------------------------------------+------------------------------------- Reporter: dsf | Owner: (none) Type: task | Status: new Priority: normal | Milestone: Component: Core Libraries | Version: 8.0.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Documentation | Unknown/Multiple bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by dsf): I would add: It is assumed that the argument function is transitive. A function like `not (a == 1 && b == 1)` will give a result you might not expect: {{{#!hs
let notBoth1 a b = not (a == 1 && b == 1) groupBy notBoth1 [1,1,2,3,1,1,4,5,6,1] [[1],[1,2,3],[1],[1,4,5,6],[1]] }}} rather than {{{#!hs [[1],[1,2,3,1],[1,4,5,6,1]] }}}
-- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13593#comment:8 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler