Boolean Used As Array

Booleans, true and false are not an array, but it is possible to use the array syntax with it. The values are then always null, and since PHP 7.4, a warning is emitted.

PHP code

<?php

// var_dump(true[0]); is not a valid PHP syntax

const MY_CONSTANT = true;
var_dump(MY_CONSTANT[0]);

?>

Before

NULL

After

PHP Warning:  Trying to access array offset on true

Warning: Trying to access array offset on null
PHP

PHP version change

This behavior changed in 7.4

Error Messages

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