Proposal: Use (.) and id from Control.Category in Prelude

Carter Charbonneau zcarterc at
Mon Jul 21 16:25:19 UTC 2014

On 06/14/2014 02:15 PM, Carter Charbonneau wrote:
> (.) and id are generalized in the Category class in Control.Category. In
> the past, many libraries have instructed users to use (.) and id from
> Control.Category for composition of their types. Importing these types
> into Prelude shouldn't break existing code, and makes libraries that use
> Category easier to use.
> Discussion period: 4 weeks

This proposal has very little support, +0/-4 (or +1/-4 counting posts 
without an explicit vote). The negative points were that it would make 
error messages worse and Control.Category is PolyKinded which would make 
standardizing Prelude more difficult.

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