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Today's Topics:
1. Re: phantom type (Theodore Lief Gannon)
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Message: 1
Date: Sat, 31 Mar 2018 20:31:46 +0000
From: Theodore Lief Gannon <[email protected]>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <[email protected]>
Subject: Re: [Haskell-beginners] phantom type
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<cajopsucxadbprc+jccg54p1_-h9tsqchs-2vzsl4ey_bswc...@mail.gmail.com>
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Directly relevant blog:
https://www.benjamin.pizza/posts/2017-12-15-functor-functors.html
On Sat, Mar 31, 2018, 1:41 AM Francesco Ariis <[email protected]> wrote:
> On Sat, Mar 31, 2018 at 07:54:50AM +0000, PICCA Frederic-Emmanuel wrote:
> > I create a method
> >
> > myMethod :: MyData Collect -> IO ()
> >
> > but I want my method to work for MyData Collect and Mydata
> Caracterization but not Unchecked.
> >
> > So It seems to me that I can not just do
> >
> > myMethod :: MyData t -> IO ()
> >
> >
> > what is the right way to solve this problem ?
>
> Hello Frederic,
> I am in a rush so I cant write a minimal example, but wouldn't
> a typeclass + make Collect and Cara instances of that typeclass do?
> -F
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