lib/rotjs-library/src/js/string.js

/**
 * @returns {string} First letter capitalized
 */
String.prototype.capitalize = function() {
	return this.charAt(0).toUpperCase() + this.substring(1);
}

/** 
 * Left pad
 * @param {string} [character="0"]
 * @param {int} [count=2]
 */
String.prototype.lpad = function(character, count) {
	var ch = character || "0";
	var cnt = count || 2;

	var s = "";
	while (s.length < (cnt - this.length)) { s += ch; }
	s = s.substring(0, cnt-this.length);
	return s+this;
}

/** 
 * Right pad
 * @param {string} [character="0"]
 * @param {int} [count=2]
 */
String.prototype.rpad = function(character, count) {
	var ch = character || "0";
	var cnt = count || 2;

	var s = "";
	while (s.length < (cnt - this.length)) { s += ch; }
	s = s.substring(0, cnt-this.length);
	return this+s;
}

/**
 * Format a string in a flexible way. Scans for %s strings and replaces them with arguments. List of patterns is modifiable via String.format.map.
 * @param {string} template
 * @param {any} [argv]
 */
String.format = function(template) {
	var map = String.format.map;
	var args = Array.prototype.slice.call(arguments, 1);

	var replacer = function(match, group1, group2, index) {
		if (template.charAt(index-1) == "%") { return match.substring(1); }
		if (!args.length) { return match; }
		var obj = args[0];

		var group = group1 || group2;
		var parts = group.split(",");
		var name = parts.shift();
		var method = map[name.toLowerCase()];
		if (!method) { return match; }

		var obj = args.shift();
		var replaced = obj[method].apply(obj, parts);

		var first = name.charAt(0);
		if (first != first.toLowerCase()) { replaced = replaced.capitalize(); }

		return replaced;
	}
	return template.replace(/%(?:([a-z]+)|(?:{([^}]+)}))/gi, replacer);
}

String.format.map = {
	"s": "toString"
}

/**
 * Convenience shortcut to String.format(this)
 */
String.prototype.format = function() {
	var args = Array.prototype.slice.call(arguments);
	args.unshift(this);
	return String.format.apply(String, args);
}