Removes all characters other than a-zA-Z0-9_:, the set of valid HTML tag characters. Transforms letters to lowercase.
<?php tag_escape( $tag ); ?>
$unsafeTag = "#1 Best! Movies! EVER!!!$@#%#$"; $safeTag = tag_escape($unsafeTag); echo '$safeTag = ' . $safeTag; // returns: // $safeTag = 1bestmoviesever
tag_escape() is located in wp-includes/formatting.php
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