Generator::throw

(PHP 5 >= 5.5.0, PHP 7, PHP 8)

Generator::throwThrow an exception into the generator

Description

public Generator::throw(Throwable $exception): mixed

Throws an exception into the generator and resumes execution of the generator. The behavior will be the same as if the current yield expression was replaced with a throw $exception statement.

If the generator is already closed when this method is invoked, the exception will be thrown in the caller's context instead.

Parameters

exception

Exception to throw into the generator.

Return Values

Returns the yielded value.

Examples

Example #1 Throwing an exception into a generator

<?php
function gen() {
    echo 
"Foo\n";
    try {
        yield;
    } catch (
Exception $e) {
        echo 
"Exception: {$e->getMessage()}\n";
    }
    echo 
"Bar\n";
}
 
$gen gen();
$gen->rewind();
$gen->throw(new Exception('Test'));
?>

The above example will output:

Foo
Exception: Test
Bar