How expensive are function_exists() calls?

On Wed, Mar 4, 2009 at 1:07 PM, Kenan Sulayman kureal@kkooporation.dewrote:

Hello Mike!

Depending on how you'd define expensive, it may variate.
Normally, on websites function_exists(x) ain't expensive.

Altrought function_exists needed 0.000077009201049805 seconds to execute.
Do you think, that's pretty expensive ?

Please move this thread to the php-general mailing-list.

--
Mikko Koppanen

Update:

Reached: Average: 1.3338460335041E-5 seconds / 817542.
Shape:
Average: ( $seconds ) seconds / ( $iterations ).

--
(c) Kenan Sulayman
Freelance Designer and Programmer

Life's Live Poetry

2009/3/4 Kenan Sulayman kureal@kkooporation.de

Hello Mike!

Depending on how you'd define expensive, it may variate.
Normally, on websites function_exists(x) ain't expensive.

Altrought function_exists needed 0.000077009201049805 seconds to execute.
Do you think, that's pretty expensive ?

Your,

(c) Kenan Sulayman
Freelance Designer and Programmer

Life's Live Poetry

2009/3/4 mike mike503@gmail.com

I am trying to figure out a strategy for multiple output formats on a

site, and it seems like I can have functions defined by default, but
have them defined -after- I've included the targetted format first.

However that would require

file1.php:

function foo() {}

file2.php

if(!function_exists('foo')) {
function foo() {}
}

Is this a very expensive thing to do? There would be a good number of
functions that would be leveraging this. Is it a no-no? or is it
pretty cheap?

Thanks

• mike