3v4l.org

run code in 500+ PHP versions simultaneously
<?php $int = 42; $string = ' foo'; $trimmed = trim($string); assert(!is_numeric($string)); assert(!is_numeric($trimmed)); var_dump((string)$int <=> $string); var_dump((string)$int <=> $trimmed);
Output for 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.32, 8.3.0 - 8.3.32, 8.4.1 - 8.4.23, 8.5.0 - 8.5.8
int(1) int(-1)

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110.64 ms | 1518 KiB | 4 Q