[Haskell-cafe] TypeApplications and Proxy

Henning Thielemann lemming at henning-thielemann.de
Mon Sep 14 23:41:52 UTC 2020

On Mon, 14 Sep 2020, Johannes Waldmann wrote:

>> TypeApplication depends on the
>> order in which type variables are introduced.
> https://downloads.haskell.org/ghc/latest/docs/html/users_guide/glasgow_exts.html#ordering-of-specified-variables
> The easy fix is to declare all type variables.

It still means, that libraries have to maintain order of type variables in 
order to avoid surprises in client code. Re-ordering introduction of type 
variables becomes a breaking change - But only if the client code chooses 
to use TypeApplication.

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