#10963: Beginner-targeted language extension -------------------------------------+------------------------------------- Reporter: kanetw | Owner: Type: feature request | Status: patch Priority: normal | Milestone: Component: Compiler | Version: 7.10.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D2136 Wiki Page: | -------------------------------------+------------------------------------- Comment (by takenobu): Replying to goldfire and kanetw in comment:9 and comment:10: Thank you for explaining by comments and wiki page. I recognized that multiple specialization will confuse beginners. So I like (1D, 2B, 3D) in Richard's wiki page. * 1D, 2B : I think it's better that `:type` is simply keep for beginners. * 3D : For instance, we adopt `:type-verbose` or `:tv` command. The command intuitively represents the relation between instantiation and generalization. It's good for middle users. {{{ ghci> :tv length length :: forall {t :: * -> *} {a}. Foldable t => t a -> Int Specialized: length :: [a] -> Int -- with default (2B) length :: Maybe a -> Int -- with one of any order }}} [[BR]] My decision criteria: * Basic command (:t) is priority for beginners. * Additional command (:tv) intuitively provide the relation between instantiation and generalization for middle users. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10963#comment:12 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler