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function is not described

_wp_register_meta_args_whitelist() WP 4.6.0

Deprecated from version 5.5.0. It is no longer supported and can be removed in future releases. Use _wp_register_meta_args_allowed_list(). Please consider writing more inclusive code instead.

Filters out register_meta() args based on an allowed list.

register_meta() args may change over time, so requiring the allowed list to be explicitly turned off is a warranty seal of sorts.

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

Array. Filtered arguments.

Usage

_wp_register_meta_args_whitelist( $args, $default_args );
$args(array) (required)
Arguments from register_meta().
$default_args(array) (required)
Default arguments for register_meta().

Changelog

Since 4.6.0 Introduced.
Deprecated Since 5.5.0 Use _wp_register_meta_args_allowed_list() instead.
Please consider writing more inclusive code.

Code of _wp_register_meta_args_whitelist() WP 5.7.1

<?php
function _wp_register_meta_args_whitelist( $args, $default_args ) {
	_deprecated_function( __FUNCTION__, '5.5.0', '_wp_register_meta_args_allowed_list()' );

	return _wp_register_meta_args_allowed_list( $args, $default_args );
}