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Problems with returning true or false in eval()'d code

Posted on 16th Feb 2014 07:03 pm by admin

Hi guys,

Would appreciate some help with a problem when running eval() on a function that should return true or false.

From php.net:
Quoteeval() returns NULL unless return is called in the evaluated code, in which case the value passed to return is returned.
Not sure if I'm missing something here but the following code illustrates that the function returns true/false as expected when run directly. However, the same function run using eval() never returns true:

Code: <?php

// Function to test what eval() returns...
function test()
{

$test = rand(1, 3);
return ($test === 1) ? TRUE : FALSE;

}

$eval = "test();";
$test = eval($eval); # expect this should set $test to TRUE for 1 in 3 attempts

echo ($test) ? 'eval returned true' : 'eval returned FALSE or NULL <br />';

// Now retest the function by calling it directly, not through eval...
$test2 = test();
echo ($test2) ? 'test returned TRUE' : 'test returned FALSE or NULL <br />'; # this behaves as expected...

?>
Hopefully it's something ridiculously obvious to someone out there...

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