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run code in 500+ PHP versions simultaneously
<?php function convert(string $txt): string { do { $txt = preg_replace_callback_array( [ '~\[([bi])](.*?)\[/\1]~' => fn($m) => sprintf('<%1$s>%2$s</%1$s>', $m[1], $m[2]), '~\[img](.*?)\[/img]~' => 'foo', ], $txt, -1, $count ); } while ($count); return $txt; } function foo(array $m): string { return '<img src="' . $m[1] . '">'; } echo convert("text1 [img]path/src[/img] text2 [b]bold [i]nested string[/i][/b] [img]another/path/to/file[/img] [b]nice[/b] lingering end bbtag [/b] and [b]unclosed");
Output for 7.4.0 - 7.4.33, 8.0.1 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.32, 8.3.0 - 8.3.32, 8.4.1 - 8.4.23, 8.5.0 - 8.5.8
text1 <img src="path/src"> text2 <b>bold <i>nested string</i></b> <img src="another/path/to/file"> <b>nice</b> lingering end bbtag [/b] and [b]unclosed
preferences:
102.36 ms | 1307 KiB | 4 Q