HSL difference between two colors

hslDiff.js

/**
 * Calculate the difference in hue, saturation and lightness between two colors
 * 
 * The function requires tinycolor (https://github.com/bgrins/TinyColor)
 * Example: http://jsfiddle.net/nabil_kadimi/a9cqqth0/2/
 * 
 * @param {String} s Source color in hexadecimal
 * @param {String} d Destination color in hexadecimal
 * @return {Array} Array of differences [hue, saturtion, lightness]
 */
function hslDiff(s, d) {

	s = tinycolor(s);
	d = tinycolor(d);

	var diff = [];

	for (i in ['h','s','l']){
		diff['hsl'[i]] = d.toHsl()['hsl'[i]] - s.toHsl()['hsl'[i]];
	}

	return diff;
}