[GHC] #8574: Failure to require FlexibleContexts

[GHC]

#8574: Failure to require FlexibleContexts
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        Reporter:  Feuerbach                    |            Owner:
            Type:  bug                          |           Status:  new
        Priority:  normal                       |        Milestone:
       Component:  Compiler (Parser)            |          Version:  7.6.3
      Resolution:                               |         Keywords:
Operating System:  Unknown/Multiple             |     Architecture:
 Type of failure:  GHC accepts invalid program  |  Unknown/Multiple
       Test Case:                               |       Difficulty:
        Blocking:                               |  Unknown
                                                |       Blocked By:
                                                |  Related Tickets:
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Comment (by monoidal):

 It seems this is valid Haskell 98:
 http://www.haskell.org/onlinereport/decls.html, section 4.1.3, the class
 is allowed to take `(tyvar atype1 ... atypen)` as an argument, and `atype`
 includes `Int`.

 But the [http://www.haskell.org/ghc/docs/7.6.3/html/users_guide/other-
 type-extensions.html documentation], section 7.8.2 claims Haskell 98
 requires `(class (type-variable type-variable ...))` form. So I think this
 documentation should be changed to `(class (type-variable type type
 ...))`. Do you agree?

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8574#comment:1>
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