From: 13 <one.three@...>
Date: 2006-03-22T02:12:18+09:00
Subject: Re: ! and ? in function name

Hi,

Here is an excerpt from the free online version of the Programming
Ruby book [1]:

...
Methods that act as queries are often named with a trailing ``?'',
such as instance_of?. Methods that are ``dangerous,'' or modify the
receiver, might be named with a trailing ``!''. For instance, String
provides both a chop and a chop!. The first one returns a modified
string; the second modifies the receiver in place. ``?'' and ``!'' are
the only weird characters allowed as method name suffixes.
..

[1] http://www.rubycentral.com/book/tut_methods.html

Martins

On 3/21/06, Tony <tony.moutaux@igbmc.u-strasbg.fr> wrote:
> Hi Ruby-rulez !
>
> I often look at some code, for example un rails/active_record, where
> functions name end with a ? or a !
>
> Is this a special notation, meaning that the func or args or whatever
> have some treatment before/after the body ? Or to show that the function
> return a boolean (?) and the arg modified (!) ?
>
> Thanx ;)
>
> --
> Posted via http://www.ruby-forum.com/.
>
>