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<?php namespace Foo; function assert() {}
Output for 8.0.0 - 8.0.3
Fatal error: Defining a custom assert() function is not allowed, as the function has special semantics in /in/bRAbN on line 5
Process exited with code 255.
Output for 7.3.0 - 7.3.27, 7.4.0 - 7.4.16
Deprecated: Defining a custom assert() function is deprecated, as the function has special semantics in /in/bRAbN on line 5