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Date: Sat, 25 Jul 2015 21:42:50 +0900
From: Oleg <oleg@okmij.org>
To: edwin+ml-ocaml@etorok.net
Cc: caml-list@inria.fr
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Subject: Re: [Caml-list] Clever typing for client-server communication?


> > Once you have these types you might write type-level functions to
> > retrieve the components.   Here's a function that retrieves the 'src'
> > component:
> > 
> >    type 'a src = 's constraint 'a = < src: 's; .. >

> This is very useful to know, thanks!

> It'd be interesting to know how you come up with these solutions :)

This is probably a folklore, but it was mentioned on this list more than
a decade ago by Jacques Garrigue. We have used this trick extensively
in

        http://okmij.org/ftp/meta-programming/HPC.html#GE-generation

(see the description on p11 of the SCP-metamonads.pdf paper, and many
applications starting from p21)