For Programmers: Free Programming Magazines  


Home > Archive > PHP Language > October 2006 > similar at function_exist but if function_has_values









You are viewing an archived Text-only version of the thread. To view this thread in it's original format and/or if you want to reply to this thread please [click here]

 

Author similar at function_exist but if function_has_values
artev

2006-10-30, 7:02 pm

I want to verified when one function myFunction return a value (link).
The function can return a string (link) or nothing.


If I want know if function exist I can write this
if function_exist(myFunction) ...

now I want know if the return of the function is some or nothing:

if function_has_value(myFunction)
{... code }
or similar
if funtion_return_value(myFunction)
{... code }
or
if function_not_return_no_value(myFunction)

{... code }


how I can resolve?
Rik

2006-10-30, 7:02 pm

artev wrote:
> I want to verified when one function myFunction return a value (link).
> The function can return a string (link) or nothing.
>
>
> If I want know if function exist I can write this
> if function_exist(myFunction) ...
>
> now I want know if the return of the function is some or nothing:
>
> if function_has_value(myFunction)
> {... code }
> or similar
> if funtion_return_value(myFunction)
> {... code }
> or
> if function_not_return_no_value(myFunction)

> {... code }
>
>
> how I can resolve?


Not easily, wether a function returns something is often dependant on the
input (allthough more user-defined functions should return false/thrigger
an error, often forgotten/skipped by most people).

If you know the function name, and the parameters, you can offcourse:
$returns_something =
is_null(call_user_func($name,$parameter1
[,$parameter2[,..]]));
Allthough, when it returns null (which is rare), it will say the function
returns nothing).

--
Rik Wasmus


artev

2006-10-30, 7:02 pm

-Code for test-
<?php function test($aa)
{
if (is_null($aa))
print 'I AM NULL';
else
print 'NO';
}
?>

<?php test( my_function(par1; par2, par3) ); ?>

-Code normal--
<?php my_function(par1; par2, par3); ?>

While the code normal write link or nothing the code test,
write always I AM NULL;

-----------------
If I use this code:
if (is_string($aa))
print 'I AM STRING';
else
print 'NO';
write always NO:
So when I have a link the test said: isn't a string and is null;
When I have nothing the test said: isn't a string(exact) and is null
(exact);


artev

2006-10-30, 7:02 pm

-Code for test-
<?php function test($my_fun)
{
if (is_null($my_fun))
print 'I AM NULL';
else
print 'NO';
}
?>

<?php test( my_function(par1; par2, par3) ); ?> (point A)

-Code normal--
<?php my_function(par1; par2, par3); ?>

While the code normal write link or nothing the code test,
write always I AM NULL;

-----------------
If I use this code:
if (is_string($my_fun))
print 'I AM STRING';
else
print 'NO';
write always NO:
So when I have a link the test said: isn't a string and is null;
When I have nothing the test said: isn't a string(exact) and is null
(exact);

AND OTHER PROBLEM:
in the code test the point A repeat the value of the my_function:
I not want that; I want only use the if (is_null($my_fun))
and not the value of $my_fun
..
Sponsored Links







Also available: Server administration forum archive | Web Design forum archive | Software forum archive | Hardware reviews archive

Copyright 2009 codecomments.com