Determine whether a meta key is protected.

Signature

is_protected_meta( $meta_key, $meta_type = null )
meta_key
 (string) Meta key
meta_type
 (null)
Default: null

Return

(boolean) True if the key is protected, false otherwise.

Source

function is_protected_meta( $meta_key, $meta_type = null ) {
	$protected = ( '_' == $meta_key[0] );

	/**
	 * Filter whether a meta key is protected.
	 *
	 * @since 3.2.0
	 *
	 * @param bool   $protected Whether the key is protected. Default false.
	 * @param string $meta_key  Meta key.
	 * @param string $meta_type Meta type.
	 */
	return apply_filters( 'is_protected_meta', $protected, $meta_key, $meta_type );
}
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