Opened 5 years ago

Closed 5 years ago

#4271 closed bug (fixed)

Cannot declare multiparameter type class with TypeOperators.

Reported by: Khudyakov Owned by:
Priority: normal Milestone:
Component: Compiler Version: 6.12.3
Keywords: Cc:
Operating System: Unknown/Multiple Architecture: Unknown/Multiple
Type of failure: None/Unknown Test Case:
Blocked By: Blocking:
Related Tickets: Differential Rev(s):
Wiki Page:


This code lead to error message: "Malformed instance header"

{-# LANGUAGE TypeOperators #-}
{-# LANGUAGE MultiParamTypeClasses #-}

class f :<: g

instance () :<: ()

If instance declaration changed to code below it compiles just fine.

instance (:<:) () ()

Change History (1)

comment:1 Changed 5 years ago by simonpj

  • Resolution set to fixed
  • Status changed from new to closed

Happily this is fixed in the HEAD. Will be in the next release.


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