Proposal: Add default instances for Functor and Applicative

Simon Peyton-Jones simonpj at
Sun Sep 25 02:51:19 CEST 2011

|  With regard to [1], default superclass instances, is there already a plan to 
| implement them? And if so, when is it expected to be finished? 
|  [1]

It definitely won't be in 7.4 I'm afraid.  

One thing that would be motivating would be a list of people who actively want default superclass instances and why you want them.  My own priorities for implementing stuff are much influenced by what GHC's users seem to value.  I've added an "Applications" section to [1]; do add yourself and sketch how you'd use the new feature.


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