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<?php $a = 'hello, [how]. please don\'t remove [are] you?'; echo preg_replace('#\s*\[.+\]\s*#b', ' ', $a);
Output for 5.2.3 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.7
Warning: preg_replace(): Unknown modifier 'b' in /in/4GtEd on line 4
Output for 4.4.3 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.2
<br /> <b>Warning</b>: preg_replace() [<a href='function.preg-replace'>function.preg-replace</a>]: Unknown modifier 'b' in <b>/in/4GtEd</b> on line <b>4</b><br />
Output for 4.3.11, 4.4.0 - 4.4.2
<br /> <b>Warning</b>: preg_replace(): Unknown modifier 'b' in <b>/in/4GtEd</b> on line <b>4</b><br />
Output for 4.3.0 - 4.3.10
<br /> <b>Warning</b>: Unknown modifier 'b' in <b>/in/4GtEd</b> on line <b>4</b><br />
preferences:
305.61 ms | 401 KiB | 461 Q