_deprecated_function()

_deprecated_function( string $function_name, string $version, string $replacement = '' )

function _deprecated_function( $function_name, $version, $replacement = '' ) {

	/**
	 * Fires when a deprecated function is called.
	 *
	 * @since 2.5.0
	 *
	 * @param string $function_name The function that was called.
	 * @param string $replacement   The function that should have been called.
	 * @param string $version       The version of WordPress that deprecated the function.
	 */
	do_action( 'deprecated_function_run', $function_name, $replacement, $version );

	/**
	 * Filters whether to trigger an error for deprecated functions.
	 *
	 * @since 2.5.0
	 *
	 * @param bool $trigger Whether to trigger the error for deprecated functions. Default true.
	 */
	if ( WP_DEBUG && apply_filters( 'deprecated_function_trigger_error', true ) ) {
		if ( function_exists( '__' ) ) {
			if ( $replacement ) {
				$message = sprintf(
					/* translators: 1: PHP function name, 2: Version number, 3: Alternative function name. */
					__( 'Function %1$s is <strong>deprecated</strong> since version %2$s! Use %3$s instead.' ),
					$function_name,
					$version,
					$replacement
				);
			} else {
				$message = sprintf(
					/* translators: 1: PHP function name, 2: Version number. */
					__( 'Function %1$s is <strong>deprecated</strong> since version %2$s with no alternative available.' ),
					$function_name,
					$version
				);
			}
		} else {
			if ( $replacement ) {
				$message = sprintf(
					'Function %1$s is <strong>deprecated</strong> since version %2$s! Use %3$s instead.',
					$function_name,
					$version,
					$replacement
				);
			} else {
				$message = sprintf(
					'Function %1$s is <strong>deprecated</strong> since version %2$s with no alternative available.',
					$function_name,
					$version
				);
			}
		}

		wp_trigger_error( '', $message, E_USER_DEPRECATED );
	}
}