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<?php namespace foo; var_dump(function_exists('foo\strlen')); var_dump(strlen('x')); var_dump(function_exists('foo\strlen')); if (true) { function strlen($x) { return 42; } var_dump(function_exists('foo\strlen')); } var_dump(strlen('x'));
Output for 8.0.1 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
bool(false) int(1) bool(false) bool(true) int(42)

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