Reduce a string's length by clipping characters off the end, adding optional characters to the end such as ellipsis

string.prototype.clip.js

/*
** String prototype for clipping text and optionally adding ellipsis
** Does not modify original variable
** -Example-
** var thisStr = 'Some string of text';
** var newStr = thisStr.clip(10, '...', true); // Some...
** var newStr = thisStr.clip(15, '...', true); // Some string of...
*/
String.prototype.clip = function(len/* Number */, str/* String */, bound/* Boolean */) {
	var origLen = len;
	if(this.length > len) {
		var text = '';
		var delimiters = [' ', '-', '_', '.']
		if(bound) {
			while(text == '' && len > 0) {
				var match = false;
				var delimit = false;
				for(var x=0; x < delimiters.length; x+=1) {
				    if(this.substr(len,1) == delimiters[x]) {
						match = true;
				    }
					if(this.indexOf(delimiters[x]) > -1) {
						delimit = true;
					}
				}
				if(delimit == false || match == true) {
				    text = this.substr(0, len);
				} else {
				    len--;
				}
				if(len == 0) {
					text = this.substr(0, origLen);
				}
			}
		} else {
			text = this.substr(0, len);
		}
		
		if(str && str != "") {
			text = text + str;
		}
		return text;
	}
	return this;
}