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Date: Wed, 5 Nov 2003 02:13:05 -0800
From: Issac Trotts <ijtrotts@ucdavis.edu>
To: caml-list@inria.fr
Subject: Re: [Caml-list] function overloading
Message-ID: <20031105101305.GA28600@ucdavis.edu>
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On Wed, Nov 05, 2003 at 12:57:18AM -0800, Dustin Sallings wrote:
> 
> 	I swear I found an example demonstrating how to do pattern matching 
> based on the type of an argument, but every pattern matching example I 
> can find now seems to be focused on value and not type.
> 
> 	I'm trying to do something like this:
> 
> let print_poly x = match x with
>     | (x: bool) -> print_bool x
>     | (x: int) ->  print_int x
> ;;
> 
> 	Can someone tell me what I'm doing wrong (or perhaps tell me why I 
> shouldn't be doing this at all)?

You can do this:

type bool_or_int = Bool of bool | Int of int;;

let print_bool b = print_string (if b then "true" else "false");;

let print_poly x = match x with 
    Bool b -> print_bool b
  | Int i -> print_int i;;

let x = Bool true;;

print_poly x;;

-- 
Issac Trotts

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