Am Montag, den 16.05.2016, 17:55 +0100 schrieb Guillaume Hennequin:
> Thanks all for your prompt answers;
> 
> > See the FAQ entry, "How to write a function with polymorphic arguments?"
> >   https://ocaml.org/learn/faq.html#Howtowriteafunctionwithpolymorphicarguments
> 
> this page explains how to do it with records or objects, but ends with a 
> mysterious "FIXME: a direct way now exists". Does anyone know what this might 
> refer to?

What you would need is

let print_both : ('a . 'a -> 'a) -> unit = ...

i.e. the scope of the quantifier is restricted to the first argument.
This doesn't exist to my knowledge. Maybe it was part of some dev
version?

Gerd
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Gerd Stolpmann, Darmstadt, Germany    gerd@gerd-stolpmann.de
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Company homepage:       http://www.gerd-stolpmann.de
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