#15354: QuantifiedConstraints not fully described in manual
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Reporter: goldfire | Owner: (none)
Type: bug | Status: new
Priority: normal | Milestone: 8.6.1
Component: Documentation | Version: 8.5
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: |
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Comment (by AntC):
Replying to [comment:1 Simon Peyton Jones
{{{ This is a documentation-only fix, addressing Trac #15354. }}}
Thanks Simon, is there a typo? {{{ class ::= ... | [forall tyavrs .] [context =>] qtycls inst1 ... instn | [forall tyavrs .] [context =>] tyvar inst1 ... instn }}} should be `| [forall tyvars .] ...`? (I think this has come through from the github proposal.) So to know if some code is using `QuantifiedConstraints`: either there's a `context =>` or a `forall` (or both). If neither appear (despite having `{-# LANGUAGE QuantifiedConstraints #-}`), then it's a regular class appearing in a context, whatever "regular" means ;-). -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15354#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler