From: "Till Varoquaux" <till.varoquaux@gmail.com>
To: "Nicolas Pouillard" <nicolas.pouillard@gmail.com>
Cc: tmp123 <tmp123@menta.net>, caml-list <caml-list@inria.fr>
Subject: Re: [Caml-list] log function without evaluate arguments
Date: Tue, 6 Nov 2007 13:40:19 -0500 [thread overview]
Message-ID: <9d3ec8300711061040l424aac69y4b859a029d815089@mail.gmail.com> (raw)
In-Reply-To: <1194373338-sup-9994@ausone.local>
On 11/6/07, Nicolas Pouillard <nicolas.pouillard@gmail.com> wrote:
> Excerpts from tmp123's message of Tue Nov 06 18:05:48 +0100 2007:
> > Hello,
> >
> > In order to implement a function that prints log messages only, by
> > example, if a boolean flag is true, and does nothing elsewhere, I've
> > been reading the (long) post sequence "kprintf with user formatters"
> > (2004 Jun 30).
> >
> > In this context, "does nothing" means not convert parameters to text nor
> > evaluate them.
>
> Have a look to the Printf.ifprintf [1] function, it does exactly what you want.
>
> Regards,
>
Actually it doesn't:
log (lazy (Printf.printf "%s" (awfully_long_computation ())))
when log_val is false (or sylvain's solution, which I prefer), will
not behave like
Printf.ifprinf "%s" (awfully_long_computation ())
(it won't evaluate its arguments).
Till
--
http://till-varoquaux.blogspot.com/
next prev parent reply other threads:[~2007-11-06 18:40 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-11-06 17:05 tmp123
2007-11-06 16:57 ` Sylvain Le Gall
2007-11-06 18:25 ` [Caml-list] " Nicolas Pouillard
2007-11-06 18:40 ` Till Varoquaux [this message]
2007-11-06 18:49 ` Brian Hurt
2007-11-07 3:39 ` Christopher L Conway
2007-11-07 4:00 ` Erik de Castro Lopo
2007-11-07 4:10 ` Christopher L Conway
2007-11-07 13:42 ` Brian Hurt
2007-11-07 10:21 ` Nicolas Pouillard
2007-11-07 3:40 ` Christopher L Conway
[not found] ` <4a051d930711061938u25836a85ud28c610312e5896f@mail.gmail.com>
2007-11-07 10:31 ` tmp123
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