Re: template and NULL

From:

Greg Herlihy <greghe@pacbell.net>

Newsgroups:

comp.lang.c++.moderated

Date:

Fri, 3 Aug 2007 10:03:47 CST

Message-ID:

<C2D81E53.2937%greghe@pacbell.net>

On 8/2/07 10:28 AM, in article C2D6F3BD.2909%greghe@pacbell.net, "Greg
Herlihy" <greghe@pacbell.net> wrote:

On 8/1/07 6:20 AM, in article
1185953526.014787.80560@b79g2000hse.googlegroups.com, "Ni"
<golubev.nikolay@gmail.com> wrote:

The most straightforward way to silence the warning (aside from adding:

#undef NULL
#define NULL 0

to createObject's header file) would be to define a createObject()

function

override that the gcc compiler will select to match the createObject(NULL)
call. This override would then call the original createObject() function,
and pass it - yes, you guessed it - zero as the argument:

    inline Object createObject( void *)
    {
        return createObject( 0 );
    }

I probably should mentioned in my original response that my proposed
implementation of createObject winds up calling itself in an endless
recursion. So an "optimized" version of this routine that would call the
original createObject function might work out better:

    inline Object
    createObject( void *)
    {
        return createObject( VALIDATION_FUNCTION( 0));
    }

What the na?ve reader may think was an embarrassing mistake my part - is of
course just one of those subtle errors that I am careful to include in most
of my posts. I try to avoid posting the perfect solution whenever possible -
not only so that I can provide the original poster with the satisfaction of
debugging the "mistake" - but also as a reward to the attentive reader...
:-)

Greg

--
      [ See http://www.gotw.ca/resources/clcm.htm for info about ]
      [ comp.lang.c++.moderated. First time posters: Do this! ]