3v4l.org

run code in 300+ PHP versions simultaneously
<?php // int isn't a reserved word, right? // So this should work fine! const int = 7; // Let's try using it! var_dump( /**/int ); /* Wait, what? A parse error? Why, you might ask? (int) is a special case in the lexer. Turns out that casts are lexed specially. Why? Probably to stop the type names being reserved words... that worked out spectacularly, didn't it? The best bit, though, is that this has been around since PHP 3, so it's most likely the fault of Zeev Suraski or Andi Gutmans. Good job. */

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