From: Jon Harrop <jon@ffconsultancy.com>
To: caml-list@yquem.inria.fr
Subject: Re: [Caml-list] let rec and polymorphic functions
Date: Wed, 27 Jun 2007 10:05:10 +0100 [thread overview]
Message-ID: <200706271005.10837.jon@ffconsultancy.com> (raw)
In-Reply-To: <000e01c7b896$d3372440$6a7ba8c0@treble>
There are many problems with this. Google for ad-hoc polymorphism, polymorphic
recursion and generic printing.
On Wednesday 27 June 2007 09:40:31 David Allsopp wrote:
> out "TEST";
val out : string -> unit
> out "%d" 0;
val out : format -> int -> unit
As printf is ad-hoc polymorphic, you must supply the format specifier
immediately and OCaml will generate a custom printer for you. OCaml does not
use run-time types so you cannot have a generic print function: you must
specific print functions for each of your (possibly higher-order) types.
Also, recursive calls ossify the function to a monomorphic type, so you cannot
do polymorphic recursion in OCaml. There are workaround using recursive
modules or objects but I don't think this is what you want here.
--
Dr Jon D Harrop, Flying Frog Consultancy Ltd.
The OCaml Journal
http://www.ffconsultancy.com/products/ocaml_journal/?e
next prev parent reply other threads:[~2007-06-27 9:11 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-06-27 8:40 David Allsopp
2007-06-27 9:05 ` Jon Harrop [this message]
2007-06-27 10:14 ` [Caml-list] " Arnaud Spiwack
[not found] <20070627100004.9E0DABC73@yquem.inria.fr>
2007-06-27 10:24 ` David Allsopp
2007-06-27 11:12 ` Jeremy Yallop
2007-06-27 11:29 ` David Allsopp
2007-06-27 12:00 ` Virgile Prevosto
2007-06-27 13:00 ` Jeremy Yallop
2007-06-27 13:12 ` Jon Harrop
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