rest_validate_value_from_schema

 * @param WP_REST_Request $request
 * @param string          $param
 * @return mixed
 */
function rest_parse_request_arg( $value, $request, $param ) {
	$is_valid = rest_validate_request_arg( $value, $request, $param );

	if ( is_wp_error( $is_valid ) ) {
		return $is_valid;
	}

	$value = rest_sanitize_request_arg( $value, $request, $param );

	return $value;
}

/**
 * Determines if an IP address is valid.
 *
 * Handles both IPv4 and IPv6 addresses.
 *
 * @since 4.7.0
 *
 * @param string $ip IP address.
 * @return string|false The valid IP address, otherwise false.
 */
function rest_is_ip_address( $ip ) {
	$ipv4_pattern = '/^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$/';

	if ( ! preg_match( $ipv4_pattern, $ip ) && ! Requests_IPv6::check_ipv6( $ip ) ) {
		return false;
	}

	return $ip;
}

/**
 * Changes a boolean-like value into the proper boolean value.
 *
 * @since 4.7.0
 *
 * @param bool|string|int $value The value being evaluated.
 * @return boolean Returns the proper associated boolean value.
 */
function rest_sanitize_boolean( $value ) {
	// String values are translated to `true`; make sure 'false' is false.
	if ( is_string( $value ) ) {
		$value = strtolower( $value );
		if ( in_array( $value, array( 'false', '0' ), true ) ) {
			$value = false;
		}
	}

	// Everything else will map nicely to boolean.
	return (bool) $value;
}

/**
 * Determines if a given value is boolean-like.
 *
 * @since 4.7.0
 *
 * @param bool|string $maybe_bool The value being evaluated.
 * @return boolean True if a boolean, otherwise false.
 */
function rest_is_boolean( $maybe_bool ) {
	if ( is_bool( $maybe_bool ) ) {
		return true;
	}

	if ( is_string( $maybe_bool ) ) {
		$maybe_bool = strtolower( $maybe_bool );

		$valid_boolean_values = array(
			'false',
			'true',
			'0',
			'1',
		);

		return in_array( $maybe_bool, $valid_boolean_values, true );
	}

	if ( is_int( $maybe_bool ) ) {
		return in_array( $maybe_bool, array( 0, 1 ), true );
	}

	return false;
}

/**
 * Determines if a given value is integer-like.
 *
 * @since 5.5.0
 *
 * @param mixed $maybe_integer The value being evaluated.
 * @return bool True if an integer, otherwise false.
 */
function rest_is_integer( $maybe_integer ) {
	return is_numeric( $maybe_integer ) && round( floatval( $maybe_integer ) ) === floatval( $maybe_integer );
}

/**
 * Determines if a given value is array-like.
 *
 * @since 5.5.0
 *
 * @param mixed $maybe_array The value being evaluated.
 * @return bool
 */
function rest_is_array( $maybe_array ) {
	if ( is_scalar( $maybe_array ) ) {
		$maybe_array = wp_parse_list( $maybe_array );
	}

	return wp_is_numeric_array( $maybe_array );
}

/**
 * Converts an array-like value to an array.
 *
 * @since 5.5.0
 *
 * @param mixed $maybe_array The value being evaluated.
 * @return array Returns the array extracted from the value.
 */
function rest_sanitize_array( $maybe_array ) {
	if ( is_scalar( $maybe_array ) ) {
		return wp_parse_list( $maybe_array );
	}

	if ( ! is_array( $maybe_array ) ) {
		return array();
	}

	// Normalize to numeric array so nothing unexpected is in the keys.
	return array_values( $maybe_array );
}

/**
 * Determines if a given value is object-like.
 *
 * @since 5.5.0
 *
 * @param mixed $maybe_object The value being evaluated.
 * @return bool True if object like, otherwise false.
 */
function rest_is_object( $maybe_object ) {
	if ( '' === $maybe_object ) {
		return true;
	}

	if ( $maybe_object instanceof stdClass ) {
		return true;
	}

	if ( $maybe_object instanceof JsonSerializable ) {
		$maybe_object = $maybe_object->jsonSerialize();
	}

	return is_array( $maybe_object );
}

/**
 * Converts an object-like value to an object.
 *
 * @since 5.5.0
 *
 * @param mixed $maybe_object The value being evaluated.
 * @return array Returns the object extracted from the value.
 */
function rest_sanitize_object( $maybe_object ) {
	if ( '' === $maybe_object ) {
		return array();
	}