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<?php $tests = [ 'foo', 'fooBar', 'foo123', '123Foo', 'fooBar123', 'foo123Bar', '123FooBar', ]; var_export( preg_replace( '/(?:\d++|[A-Za-z]?[a-z]++)\K(?!$)/', '-', $tests ) );
Output for 8.0.1 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.26, 8.4.1 - 8.4.13
array ( 0 => 'foo', 1 => 'foo-Bar', 2 => 'foo-123', 3 => '123-Foo', 4 => 'foo-Bar-123', 5 => 'foo-123-Bar', 6 => '123-Foo-Bar', )
preferences:
86.33 ms | 407 KiB | 5 Q