DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma;
	h=message-id:date:from:user-agent:mime-version:to:cc:subject
	:references:in-reply-to:content-type:content-transfer-encoding;
	b=SejCQvVa1XoKuic6Mqz4zzRc1Vooj88fOKYSh2IHv2KhfuGH5W9Oc8W53gGDBQsEoq
	9T3/KW1S663gdT07CLg96inLL/mlMdjTLXV/KuGORPHkrsc2dfkx58MUQ9TbfkVnBpzo
	KkrnX4+8pJCjXufRITwg4N+JQJQaHmuf+7cO4=
Message-ID: <4942FE09.1040508 at gmail.com>
Date: Fri, 12 Dec 2008 18:12:57 -0600
From: Edgar Friendly <thelema314 at gmail.com>
MIME-Version: 1.0
To: Mike Spivey <mike at comlab.ox.ac.uk>
Subject: Re: [Lablgtk] Binding for gtkSourceView-2.0
References: <4940ED23.9010808 at comlab.ox.ac.uk> <49410E1F.1080203 at cea.fr>
	<49411B69.7080600@comlab.ox.ac.uk>
In-Reply-To: <49411B69.7080600 at comlab.ox.ac.uk>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Cc: Benjamin Monate <benjamin.monate at cea.fr>, lablgtk at yquem.inria.fr

Mike Spivey wrote:
> (1) Is there a fixed rule for what methods take () as a final parameter?
>  Methods with side effects and no arguments, yes; but what about methods
> like
> 
> 	method guess_language :
> 	  ?filename:string -> ?content_type:string
> 	    -> unit -> source_language (* or raise Not_found *)
> 
> that have no side-effects and only optional arguments?
> 
Yes on methods with only optional parameters.  Unless there's a
non-optional parameter, uses without arguments could be partial.
General rule: use () as final parameter when necessary - when you need
to be able to force non-partial application.

> (2) On the same example: if a C method with type t may return NULL, then
> we have multiple possibilities in OCaml:
> 
> 	(i)   return "t option"
> 	(ii)  return "t", but raise Not_found if the result is NULL
> 	(iii) if t = string, then return the empty string for NULL
> 
> A similar question applies to arguments that may be NULL.  Is there a
> rule that I should follow?
> 
Depends on whether returning NULL is really exceptional, but probably
not (iii), unless the empty string really is meant by a NULL response.

E.

_______________________________________________
Lablgtk mailing list
Lablgtk@yquem.inria.fr
http://yquem.inria.fr/cgi-bin/mailman/listinfo/lablgtk