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run code in 200+ php & hhvm versions
<?php declare(strict_types=1); class toStr { private $str; public function __construct( $str ) { $this->str = $str; } public function __toString() { return $this->str; } } function strictly( string $str ) { return $str; } strictly( new toStr('hi'));
based on reEEd
Output for 7.1.25 - 7.3.3
Fatal error: Uncaught TypeError: Argument 1 passed to strictly() must be of the type string, object given, called in /in/gU06F on line 20 and defined in /in/gU06F:16 Stack trace: #0 /in/gU06F(20): strictly(Object(toStr)) #1 {main} thrown in /in/gU06F on line 16
Process exited with code 255.