Injective type families

[Simon Peyton Jones]

I agree!

|  -----Original Message-----
|  From: Richard Eisenberg [mailto:eir at cis.upenn.edu]
|  Sent: 11 January 2016 16:35
|  To: Jan Stolarek <jan.stolarek at p.lodz.pl>
|  Cc: Simon Peyton Jones <simonpj at microsoft.com>; GHC developers <ghc-
|  devs at haskell.org>
|  Subject: Re: Injective type families
|  
|  I'm joining this conversation late, but I favor TypeFamilyDependencies
|  over InjectiveTypeFamilies. We use the annotations for things other
|  than injectivity! For example,
|  
|  > type family Plus a b = r | r a -> b, r b -> a
|  
|  is not injective under any common understanding of the word. And the
|  argument-to-argument dependencies Simon has been musing about are even
|  further from the meaning of "injective".
|  
|  Richard
|  
|  On Jan 8, 2016, at 6:43 AM, Jan Stolarek <jan.stolarek at p.lodz.pl>
|  wrote:
|  
|  >> Is "InjectiveTypeFamilies" a good name for this?  Or
|  "TypeFamilyDependencies"?  Or what?
|  > My vote for "InjectiveTypeFamilies".
|  >
|  > Janek
|  >
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