#15081: Finite list becomes infinite after maping fractional function for high numbers -------------------------------------+------------------------------------- Reporter: Onsed | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.2.2 Resolution: | Keywords: Operating System: Linux | Architecture: x86_64 Type of failure: Incorrect result | (amd64) at runtime | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by svenpanne): Hmmm, even with the improved instances, aren't we just shifting the problem by one bit? The underlying problem stays: You can write more precise Integers than Double can represent, and enumerating floating point numbers is inherently fragile. People tend to assume initially that {{{#!haskell map (/2) [9007199254740990..9007199254740991] }}} behaves like {{{#!haskell map ((/2) . fromIntegral) [9007199254740990..9007199254740991] }}} which is something different because of defaulting/typing rules. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15081#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler