Truncate strings of text and append a link to show the full text

gistfile1.js

var len = 100;
var p = document.getElementsByClassName('truncate');
if (p) {
  for(i=0;i<p.length;i++){
    var trunc = p[i].innerHTML;
    if (trunc.length > len) {

      /* Truncate the content of the P, then go back to the end of the
         previous word to ensure that we don't truncate in the middle of
         a word */
      trunc = trunc.substring(0, len);
      trunc = trunc.replace(/\w+$/, '');

      /* Add an ellipses to the end and make it a link that expands
         the paragraph back to its original size */
      trunc += '<a href="#" ' +
        'onclick="this.parentNode.innerHTML=' +
        'unescape(\''+escape(p[i].innerHTML)+'\');return false;">' +
        '...<\/a>';
      p[i].innerHTML = trunc;
    }
  }
}