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<?php preg_match('~a(?=(b|b\K))b~', 'abc', $matches); print_r($matches); preg_match('~a(?=(bx|b\K))b~', 'abc', $matches); print_r($matches);
Output for 8.5.0 - 8.5.1
Warning: preg_match(): Compilation failed: \K is not allowed in lookarounds (but see PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK) at offset 13 in /in/g4Ldi on line 3 Warning: preg_match(): Compilation failed: \K is not allowed in lookarounds (but see PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK) at offset 14 in /in/g4Ldi on line 6
Output for 8.2.0 - 8.2.29, 8.3.0 - 8.3.28, 8.4.1 - 8.4.14, 8.4.16
Array ( [0] => ab [1] => b ) Array ( [0] => [1] => b )
Output for 8.4.15
/bin/php-8.4.15: /usr/lib/libm.so.6: version `GLIBC_2.38' not found (required by /bin/php-8.4.15) /bin/php-8.4.15: /usr/lib/libm.so.6: version `GLIBC_2.35' not found (required by /bin/php-8.4.15) /bin/php-8.4.15: /usr/lib/libc.so.6: version `GLIBC_2.34' not found (required by /bin/php-8.4.15) /bin/php-8.4.15: /usr/lib/libc.so.6: version `GLIBC_2.38' not found (required by /bin/php-8.4.15)
Process exited with code 1.
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