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<?php $text = 'say hello to @elise and @john'; function replace_at_symbol($matches){ $username = str_replace("@", "", $matches[0]); return '<a href="/profile/'.$username.'">'.$matches[0].'</a>';} $output = preg_replace_callback("/([@][a-zA-Z-0-9]+)/", "replace_at_symbol", $text); echo $output; ?>
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.12 - 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 - 8.3.6
say hello to <a href="/profile/elise">@elise</a> and <a href="/profile/john">@john</a>

preferences:
177.92 ms | 406 KiB | 313 Q