[GHC] #12978: User guide section on AllowAmbiguousTypes should mention TypeApplications
#12978: User guide section on AllowAmbiguousTypes should mention TypeApplications -------------------------------------+------------------------------------- Reporter: mpickering | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Keywords: newcomer | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- https://downloads.haskell.org/~ghc/latest/docs/html/users_guide/glasgow_exts... #ghc-flag--XAllowAmbiguousTypes With type applications it is tempting to write {{{ class C x a where meth :: a }}} which will fail the ambiguity check as `x` is not used in any methods. One way to get around this is to use `TypeApplications` in order to specify what `x` should be at each usage of `meth`. A small section in the user guide explaining this and linking to the section on `TypeApplications` would be useful. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12978> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler
#12978: User guide section on AllowAmbiguousTypes should mention TypeApplications -------------------------------------+------------------------------------- Reporter: mpickering | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Resolution: | Keywords: newcomer Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj): Good idea! I think that would be great. Would you like to draft it? -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12978#comment:1> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler
#12978: User guide section on AllowAmbiguousTypes should mention TypeApplications -------------------------------------+------------------------------------- Reporter: mpickering | Owner: erdeszt Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Resolution: | Keywords: newcomer Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by erdeszt): * owner: (none) => erdeszt -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12978#comment:2> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler
#12978: User guide section on AllowAmbiguousTypes should mention TypeApplications -------------------------------------+------------------------------------- Reporter: mpickering | Owner: erdeszt Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Resolution: | Keywords: newcomer Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D3668 Wiki Page: | -------------------------------------+------------------------------------- Changes (by erdeszt): * differential: => Phab:D3668 -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12978#comment:3> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler
#12978: User guide section on AllowAmbiguousTypes should mention TypeApplications -------------------------------------+------------------------------------- Reporter: mpickering | Owner: erdeszt Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Resolution: | Keywords: newcomer Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D3668 Wiki Page: | -------------------------------------+------------------------------------- Comment (by Ben Gamari <ben@…>): In [changeset:"faefa7e57d543e7001457a53954c9b378a38ee60/ghc" faefa7e5/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="faefa7e57d543e7001457a53954c9b378a38ee60" documentation: fix trac issue #12978 Add reference to TypeApplications to the AllowAmbiguousType section of the user docs Reviewers: austin, bgamari Reviewed By: bgamari Subscribers: rwbarton, thomie GHC Trac Issues: #12978 Differential Revision: https://phabricator.haskell.org/D3668 }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12978#comment:4> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler
#12978: User guide section on AllowAmbiguousTypes should mention TypeApplications -------------------------------------+------------------------------------- Reporter: mpickering | Owner: erdeszt Type: bug | Status: closed Priority: normal | Milestone: 8.2.1 Component: Compiler | Version: 8.0.1 Resolution: fixed | Keywords: newcomer Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D3668 Wiki Page: | -------------------------------------+------------------------------------- Changes (by bgamari): * status: new => closed * resolution: => fixed * milestone: => 8.2.1 Comment: Merged to `ghc-8.2` as well. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12978#comment:5> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler
participants (1)
-
GHC