Shorten a string and optionally truncate at the last word boundary

gistfile1.js

function truncateString( string, num, useWordBoundary ){
	var isLong      = string.length > num,
	    newString	= string.replace( /(^\s)|(\s$)/gi, '' ),
	    isOneWord	= newString.match(/\s/gi) === null;
        newString   = isLong ? newString.substr(0,num-1) : newString;
	newString   = ( useWordBoundary && isLong && !isOneWord ) ? newString.substr(0,newString.lastIndexOf(' ')) : newString;
	return  isLong ? newString +' ...' : newString;
};