Re: [GHC] #15959: If a type signature is too long to read left-to-right then let it read top-to-bottom.

27 Nov 2018

      #15959: If a type signature is too long to read left-to-right then let it read top-
to-bottom.
-------------------------------------+-------------------------------------
        Reporter:  philderbeast      |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:  8.6.3
       Component:  Compiler          |              Version:  8.6.2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Description changed by philderbeast:

Old description:
...
When pretty printing a type signature that is too long to show in one
line, can we please break the lines on the top-level punctuation of the
type signature, on {{{::}}}, {{{=>}}} and {{{->}}} as shown in the second
listing below?
{{{
FlareTiming/Task/Score.hs:186:1: warning: [-Wmissing-signatures]
    Top-level binding with no type signature:
      showMax :: (Reflex t, Functor f) =>
                 (a -> b)
                 -> (f b -> b -> c) -> Dynamic t (f a) -> Dynamic t a ->
Dynamic t c
    |
186 | showMax getField f pt points =
    | ^^^^^^^
}}}
{{{
FlareTiming/Task/Score.hs:186:1: warning: [-Wmissing-signatures]
    Top-level binding with no type signature:
      showMax
        :: (Reflex t, Functor f)
        => (a -> b)
        -> (f b -> b -> c)
        -> Dynamic t (f a)
        -> Dynamic t a
        -> Dynamic t c
|
186 | showMax getField f pt points =
    | ^^^^^^^
}}}
If a type signature is too long to display in one line and read left-to-
right then please let it read top-to-bottom.
New description:

 When pretty printing a type signature that is too long to show in one
 line, can we please break the lines on the top-level punctuation of the
 type signature, on {{{::}}}, {{{=>}}} and {{{->}}} as shown in the second
 listing below?

 {{{
 FlareTiming/Task/Score.hs:186:1: warning: [-Wmissing-signatures]
     Top-level binding with no type signature:
       showMax :: (Reflex t, Functor f) =>
                  (a -> b)
                  -> (f b -> b -> c) -> Dynamic t (f a) -> Dynamic t a ->
 Dynamic t c
     |
 186 | showMax getField f pt points =
     | ^^^^^^^
 }}}

 {{{
 FlareTiming/Task/Score.hs:186:1: warning: [-Wmissing-signatures]
     Top-level binding with no type signature:
       showMax
         :: (Reflex t, Functor f)
         => (a -> b)
         -> (f b -> b -> c)
         -> Dynamic t (f a)
         -> Dynamic t a
         -> Dynamic t c
     |
 186 | showMax getField f pt points =
     | ^^^^^^^
 }}}

  If a type signature is too long to display in one line and read left-to-
 right then please let it read top-to-bottom.

--

-- 
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15959#comment:1
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