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function is not described

urldecode_deep() WP 4.4.0

Navigates through an array, object, or scalar, and decodes URL-encoded values

No Hooks.

Return

Mixed. $value The decoded value.

Usage

urldecode_deep( $value );
$value(mixed) (required)
The array or string to be decoded.

Code of urldecode deep: wp-includes/formatting.php WP 5.2.2

<?php
function urldecode_deep( $value ) {
	return map_deep( $value, 'urldecode' );
}