[Caml-list] keeping parameter polymorphic

[Caml-list] keeping parameter polymorphic

[rixed]

Hello.
I can't find a way to keep f polymorphic in:

let test f = f 1, f true

that I'd like to return a int*bool from any function 'a->'a

I now this question regularly pops up, but I've tried many combinations
of "(type a)" and "'a." to no avail (ocaml 3.12.1 here).

(in real world, my function takes a generic "fold" function that I'd
like to use with various types).

Re: [Caml-list] keeping parameter polymorphic

[Gabriel Scherer]

Hi,

See the following FAQ item: "How to write a function with polymorphic
arguments?"
  http://caml.inria.fr/resources/doc/faq/core.en.html#polymorphic-arguments

On Thu, Oct 4, 2012 at 3:03 PM,  <rixed@happyleptic.org> wrote:
> Hello.
> I can't find a way to keep f polymorphic in:
>
> let test f = f 1, f true
>
> that I'd like to return a int*bool from any function 'a->'a
>
> I now this question regularly pops up, but I've tried many combinations
> of "(type a)" and "'a." to no avail (ocaml 3.12.1 here).
>
> (in real world, my function takes a generic "fold" function that I'd
> like to use with various types).
>
>
> --
> Caml-list mailing list.  Subscription management and archives:
> https://sympa.inria.fr/sympa/arc/caml-list
> Beginner's list: http://groups.yahoo.com/group/ocaml_beginners
> Bug reports: http://caml.inria.fr/bin/caml-bugs