1.2.120. Catch With Undefined Variable¶
Always initialize every variable before the try block, when they are used in a catch block. If the exception is raised before the variable is defined, the catch block may have to handle an undefined variable, leading to more chaos.
<?php
$a = 1;
try {
mayThrowAnException();
$b = 2;
} catch (\Exception $e) {
// $a is already defined, as it was done before the try block
// $b may not be defined, as it was initialized after the exception-throwing expression
echo $a + $b;
}
?>
See also catch and Non-capturing exception catches in PHP 8.
1.2.120.1. Suggestions¶
Always define the variable used in the catch clause, before the try block.
1.2.120.2. Specs¶
Short name |
Exceptions/CatchUndefinedVariable |
Rulesets |
|
Exakat since |
2.1.5 |
PHP Version |
All |
Severity |
Minor |
Time To Fix |
Quick (30 mins) |
Precision |
Very high |
Available in |