[GHC] #5927: A type-level "implies" constraint on Constraints

[GHC]

#5927: A type-level "implies" constraint on Constraints
----------------------------------------+-----------------------------------
    Reporter:  illissius                |       Owner:                  
        Type:  feature request          |      Status:  new             
    Priority:  normal                   |   Milestone:  7.6.2           
   Component:  Compiler (Type checker)  |     Version:  7.4.1           
    Keywords:                           |          Os:  Unknown/Multiple
Architecture:  Unknown/Multiple         |     Failure:  None/Unknown    
  Difficulty:  Unknown                  |    Testcase:                  
   Blockedby:                           |    Blocking:                  
     Related:                           |  
----------------------------------------+-----------------------------------

Comment(by goldfire):

 There's not really built-in compiler support for these ideas, but have you
 seen the [http://hackage.haskell.org/package/constraints constraints]
 package? It allows you to manually enter and use implication
 relationships. This doesn't solve the fundamental problem here, but it may
 help with a workaround.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/5927#comment:9>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler