php print string returned from function

Question

I have a set of php functions designed to return error text if they fail. They aren't returning the text. My function looks like this:

function poop(){
    $stuff = stuff;
    $things = things;
    if($stuff != stuff){
        return 'e: stuff does not equal stuff!';
    }
    if($things != things){
        return 'e: things do not equal things!';
    }
    // if we got this far all is good!
    return true;

}

I call my function in code like so:

if(poop() === true){
    // do things that require poop
} else {
    echo poop();
}

I thought this would return the 'e:' string as a string and print it to the page in the event that poop() did not return a boolean true value, but in reality it is not. I'm wondering if this is because of a fault in the remainder of my code or if this functionality doesn't actually exist in PHP? How should I go about ensuring I have an error returned from all my function checks? Should I use echo instead of return to print it as a string on the page?

Answer 1

Don't call your function more than once. Save its return value in a variable:

$ret = poop();
if ($ret === true) {
    // Do things that require the success.
} else {
    // Log your error message here:
    echo "An error occurred: ".$ret;
    logMessage($ret);
    // etc.
}

You may also want to look into PHP exceptions for a potentially cleaner — but probably slower — solution to error handling.

Answer 2

try this:

if( poop() !== TRUE )
    echo poop();

I used it on this code:

function poop(){ 
    $stuff = 'stuff'; 
    $things = 'things'; 
    // this is where we have wrong value
    if($stuff != 'stuff1'){ 
        return 'e: stuff does not equal stuff!'; 
    } 
    if($things != 'things'){ 
       return 'e: things do not equal things!'; 
    } 
    // if we got this far all is good! 
    return true; 

}

I hope I goood understood you, I'm newby in PHP too. :) It is also good practice to throw an exception instead of returning error msg string.