#15181: Levity Polymorphic type signatures in GHC.Prim -------------------------------------+------------------------------------- Reporter: andrewthad | Owner: (none) Type: bug | Status: closed Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.2.2 Resolution: duplicate | Keywords: | LevityPolymorphism Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: #11786 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by RyanGlScott): I'm not intimately familiar with the specifics, but I do know that `GHC.Prim` (and other code which adds magical properties to functions defined therein) is generated through the [http://git.haskell.org/ghc.git/tree/a32c8f7514c8192fa064537fb93d5a5c224991a0... genprimopcode] utility. `genprimopcode` has a convention that any type variable named `o` is levity polymorphic, so that's why `a -> o` gets a wired-in levity polymorphic type. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15181#comment:7 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler