problem returning variables from functions

saxnet

I'm having huge trouble doing something which ought to be extremely simple: returning a variable from a function. I can't see what I'm doing wrong, and starting to suspect that there's some kind of php.ini option that might be configured the wrong way - any help greatly appreciated.

I define the following function in a function library (cons_fns.php):

function double_me($input_me)
{
    $output_me = ($input_me * 2);
    echo ("<p>input: $input_me<br>" .
          "output: $output_me</p>");
    return $output_me;
}

I then call this function from a script as follows:

// include the file library
include("../cons_fns.php");

double_me(4);
echo("<p>and the function returns: $output_me</p>");

Obviously in the above example I would expect to have $output_me returned to the script with a value equal to 8. However, when I run the script I get the following HTML:

input: 4
output: 8

and the function returns:

So although the function is working (as shown by the "input: 4 output: 8"), it looks like the $output_me variable is then not being passed back to the script. This ought to be fairly basic but I have no idea what's wrong. What am I missing here? Thanks in advance for any help - saxnet

Floodboy

$output_me = double_me(4);
echo("<p>and the function returns: $output_me</p>");

dalecosp

$output_me=double_me(4);
echo("<p>and the function returns: $output_me</p>");

:eek:

dalecosp

Heh, floodboy must have a bigger pipe... 🙁

Floodboy

lol 😃 almost at same time

tekky

Originally posted by dalecosp
Heh, floodboy must have a bigger pipe... 🙁

that sounds wrong on so many levels... :p ahem goes back to being serious or something like that...

saxnet

Thanks Floodboy and dalecosp for the synchronised answers - but I'm afraid it hasn't worked 🙁 Now I get the following HTML:

input: 4
output: 8

and the function returns: $output_me

So I'm now getting just the name of the variable... weird. Any more thoughts? Something to do with global variables? Many thanks again - saxnet

Floodboy

mmmmm ...try using www.php.net/eval 🙁

tekky

Originally posted by Floodboy

$output_me = double_me(4);
echo("<p>and the function returns: $output_me</p>");

[/B]

I would think...

$output_me = double_me(4);
echo "<p>and the function returns: $output_me</p>";

woud work fine... maybe the var not evaluating is some side effect of using the () on an echo? (never tried it personally but it could happen!)

Floodboy

(never tried it personally but it could happen!)

I agree 😕

tekky

Originally posted by Floodboy
I agree 😕

actually I have tried using "text $var text" in a function argument and it had to be escaped... out and the $var .appended. to the text blocks....

same principal would apply to echo() if you chose to use it with the ()'s

saxnet

Thank you tekky for the appending suggestion. I've now tried:

$output_me = double_me(4);
echo "and the function returns: $output_me";

and

$output_me = double_me(4);
echo ("and the function returns: $output_me");

and

$output_me = double_me(4);
echo "and the function returns: " . $output_me . "";

all of which give me the same thing, ie

input: 4
output: 8

and the function returns: $output_me

So possibly the function is returning not the variable $output_me but instead a text string $output_me? Or maybe it is returning the variable $output_me, but it's set equal to "$output_me" ? Does that make sense? In which case, is my "return" statement mucked up? Argh! 😕

Tearing my hair out here. Thanks for all your help so far, everyone. Looking forward to sorting this out... - saxnet

saxnet

Floodboy, I just tried using eval as follows:

$output_me = double_me(4); 
echo ("<p>and the function returns: " . $output_me . "</p>");

$str = 'My output is $output_me.';
echo $str. "<br>\n";
eval ("\$str = \"$str\";");
echo $str. "<br>\n";

and I now get:

input: 4
output: 8

and the function returns: $output_me

My output is $output_me.
My output is $output_me.

So the variable $output_me is set equal to the text string "$output_me"... which must mean that the function is returning the text string "$output_me" when it finishes executing. Something wrong with my return statement?