[GHC] #15775: Interpreter is treating a comment character as an identifier character.

[GHC]

#15775: Interpreter is treating a comment character as an identifier character.
-------------------------------------+-------------------------------------
           Reporter:  philderbeast   |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  GHCi           |           Version:  8.4.3
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
-------------------------------------+-------------------------------------
 When bringing dhall-lang up in a REPL I stumbled across a warning about a
 character in a haddock comment. Should the interpreter be treating a
 comment character as an identifier character?

 https://github.com/dhall-lang/dhall-
 haskell/issues/646#issuecomment-430776320

 {{{#!hs
 {-# LANGUAGE CPP #-}

 data Expr s a
     -- | > Combine x y ~ x ∧ y
     = Combine (Expr s a) (Expr s a)
 }}}

 {{{
 > stack runghc -- --interactive Intersect.hs

 Intersect.hs:13:29: error:
      warning: treating Unicode character <U+2227> as identifier character
      rather than as '^' symbol [-Wunicode-homoglyph]
         -- | > Combine x y ~ x ∧ y
                                ^
    |
 13 |     -- | > Combine x y ~ x ∧ y
    |                            ^
 1 warning generated.

 > stack runghc -- --version
 runghc 8.4.3
 }}}

 There's a [https://github.com/BlockScope/unicode-homoglyph unicode-
 homoglyph] repo with the reproduction.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15775>
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