3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $exprs = [ '/[=foo=]/', '/[:foo:]/', '/[.foo.]/', ]; foreach ($exprs as $expr) { echo $expr; preg_match($expr, 'foo'); }
Output for 5.4.0 - 5.6.28, 7.0.0 - 7.1.0
/[=foo=]/ Warning: preg_match(): Compilation failed: POSIX collating elements are not supported at offset 0 in /in/5oVpP on line 11 /[:foo:]/ Warning: preg_match(): Compilation failed: POSIX named classes are supported only within a class at offset 0 in /in/5oVpP on line 11 /[.foo.]/ Warning: preg_match(): Compilation failed: POSIX collating elements are not supported at offset 0 in /in/5oVpP on line 11
Output for hhvm-3.10.0 - 3.12.0
/[=foo=]/ Warning: Compilation failed: POSIX collating elements are not supported at offset 0 in /in/5oVpP on line 11 /[:foo:]/ Warning: Compilation failed: POSIX named classes are supported only within a class at offset 0 in /in/5oVpP on line 11 /[.foo.]/ Warning: Compilation failed: POSIX collating elements are not supported at offset 0 in /in/5oVpP on line 11
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.3.29
Parse error: syntax error, unexpected '[' in /in/5oVpP on line 3
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected '[' in /in/5oVpP on line 3
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/5oVpP on line 3
Process exited with code 255.