[GHC] #13986: TypeApplications causes parse errors in @-patterns with certain Unicode characters

[GHC]

#13986: TypeApplications causes parse errors in @-patterns with certain Unicode
characters
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        Reporter:  Tikhon            |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
  (Parser)                           |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Description changed by Tikhon:

Old description:

> The following function definition works without TypeApplications but
> fails to parse with the extension enabled:
>
> {{{#!hs
> {-# LANGUAGE TypeApplications #-}
> module Mininal where
>
> foo x₁@True = 10
> }}}
>
> It also parses correctly with "x" in place of "x₁".

New description:

 The following function definition works without TypeApplications but fails
 to parse with the extension enabled:

 {{{#!hs
 {-# LANGUAGE TypeApplications #-}
 module Mininal where

 foo x₁@True = 10
 }}}

 It also parses correctly with "x" in place of "x₁".

 Parse error:

 {{{
 Minimal.hs:5:1-11: error: …
     Parse error in pattern: foo x₁ @True
 Compilation failed.
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13986#comment:1>
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