[GHC] #10803: New TypeSignatureSections extension

[GHC]

#10803: New TypeSignatureSections extension
-------------------------------------+-------------------------------------
        Reporter:  hvr               |                   Owner:
            Type:  feature request   |                  Status:  new
        Priority:  normal            |               Milestone:  7.12.1
       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 Revisions:
-------------------------------------+-------------------------------------
Description changed by hvr:

Old description:

> = Preliminary specification
>
> Have
>
>  - `(::` ''type'' `)`
>
> be syntax sugar for
>
>  - `(\x -> x ::` ''type'' `)`
>
> This new syntax extension is enabled via a new `TypeSignatureSections`
> language pragma, i.e.
>
> {{{#!hs
> {#- LANGUAGE TypeSignatureSections #-}
> }}}
>
> TODO: formalise this a bit more

New description:

 Originally [http://augustss.blogspot.co.at/2014/04/a-small-haskell-
 extension.html proposed by Lennart Augustsson]

 Incomplete work-in-progress can be found in
 [https://git.haskell.org/ghc.git/log/refs/heads/wip/T10803 wip/T10803]
 branch

 = Preliminary specification

 Have

  - `(::` ''type'' `)`

 be syntax sugar for

  - `(\x -> x ::` ''type'' `)`

 This new syntax extension is enabled via a new `TypeSignatureSections`
 language pragma, i.e.

 {{{#!hs
 {#- LANGUAGE TypeSignatureSections #-}
 }}}

 Typing judgement:

 {{{
 _________________________
  G ⊢ (:: ty) :: ty -> ty
 }}}


 TODO: formalise this a bit more

--

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10803#comment:5>
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