[Solved] Fatal error: Call to undefined function boolval()

boolval() is a PHP function that was introduced in PHP 5.5. If you try to use it on a server that runs PHP 5.4 and lower, you will get an error like this:

Fatal error: Call to undefined function boolval() in /path/to/file/file.php on line 12

To fix this error, add the following to your WordPress theme’s functions.php

 * Get the boolean value of a variable
 * @param 	mixed 	The scalar value being converted to a boolean.
 * @return 	boolean The boolean value of var.
 * @refer	http://php.net/manual/en/function.boolval.php#114013
if( !function_exists('boolval')) {
  function boolval($var){
    return !! $var;

Let me know if that helps.

Hello, I am Arun Basil Lal. Thank you for reading!

I am a WordPress product developer and creator of Image Attributes Pro. I am passionate about solving problems and travelling the world.

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  1. L. Scott Harrell says:

    Thank you very much! This fix saved me time, money and a lot of aggravation. Cheers!

  2. Rebecca says:

    Thanks mate.
    This worked. Saved me hours of messing with around.

  3. Edgar Castillo Medina says:

    Muchas gracias…funciono perfecto.
    Thanks a lot…a perfect solution!!!
    Regards from Mexico

  4. Joseph says:

    Arun, the code you supplied worked perfectly and I had my site up and running again within seconds. Thank you so much as I appreciate your support. If there is anything I can do to spread the good word and help you, please let me know. Thank you again. -Joseph

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