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<?php function a () { function b() { echo "I am b.\n"; } echo "I am a.\n"; } if (function_exists("b")) echo "b is defined.\n"; else echo "b is not defined.\n"; a(); if (function_exists("b")) echo "b is defined.\n"; else echo "b is not defined.\n";
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
b is not defined. I am a. b is defined.

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219.57 ms | 405 KiB | 306 Q