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function is not described

_deep_replace() WP 2.8.1

Perform a deep string replace operation to ensure the values in $search are no longer present

Repeats the replacement operation until it no longer replaces anything so as to remove "nested" values e.g. $subject = '%0%0%0DDD', $search ='%0D', $result ='' rather than the '%0%0DD' that str_replace would return

No Hooks.

Return

String. The string with the replaced svalues.

Usage

_deep_replace( $search, $subject );
$search(string/array) (required)
The value being searched for, otherwise known as the needle. An array may be used to designate multiple needles.
$subject(string) (required)
The string being searched and replaced on, otherwise known as the haystack.

Code of deep replace: wp-includes/formatting.php VER 5.0.3

<?php
function _deep_replace( $search, $subject ) {
	$subject = (string) $subject;

	$count = 1;
	while ( $count ) {
		$subject = str_replace( $search, '', $subject, $count );
	}

	return $subject;
}