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function is not described

_wp_translate_php_url_constant_to_key() WP 4.7.0

Translate a PHP_URL_* constant to the named array keys PHP uses.

This is an internal function for using it by WP core itself. It's not recommended to use this function in your code.

No Hooks.

Return

String|false. The named key or false.

Usage

_wp_translate_php_url_constant_to_key( $constant );
$constant(int) (required)
PHP_URL_* constant.

Changelog

Since 4.7.0 Introduced.

Code of _wp_translate_php_url_constant_to_key() WP 5.7.2

<?php
function _wp_translate_php_url_constant_to_key( $constant ) {
	$translation = array(
		PHP_URL_SCHEME   => 'scheme',
		PHP_URL_HOST     => 'host',
		PHP_URL_PORT     => 'port',
		PHP_URL_USER     => 'user',
		PHP_URL_PASS     => 'pass',
		PHP_URL_PATH     => 'path',
		PHP_URL_QUERY    => 'query',
		PHP_URL_FRAGMENT => 'fragment',
	);

	if ( isset( $translation[ $constant ] ) ) {
		return $translation[ $constant ];
	} else {
		return false;
	}
}