addClass removeClass toggleClass.js

(function()
{
  var _fnMap = {};
  
  $.fn.addClass = function(classes)
  {
    var vs = this;
    
    if(!(classes > '') || vs.length == 0)
      return this;

    (
      _fnMap[classes] || 
      (_fnMap[classes] = new Function(
        'vs',
        'var v,c,d,i=-1;while((v=vs[++i])){ if((d=v.className)){ c = " "+d+" "; v.className = d.concat(' +
          classes.replace(/(\S+)/g, '(~c.indexOf(" $1 ") ? "" : " $1"),').slice(0, -1) + 
          ') }else{ v.className="' + classes + '" } };'
        )
      )
    )(vs);
    
    return this;
  };
})();  

(function()
{
  reMap = {};
  
  $.fn.removeClass = function(classes)
  {
    var vs = this;
    
    if(!(classes > '') || vs.length == 0)
      return this;

    var re = reMap[classes] || 
      (reMap[classes] = 
        (
          (classes.indexOf(' ') < 0) ?
            ' ' + classes + ' ' : 
            new RegExp(' (?:' + 
              classes.
                replace(/[\[\]\(\)\{\}\?\!\:\|\+]/g, '\\$1').
                replace(/\s+/g, '|') +
              ')(?= )', 'g'
            )
        )
      );
    
    if(typeof(re) == 'string')
    {
      var i = -1, v, c; while((v = vs[++i]))
      {
        if((c = v.className))
          v.className = (' ' + c + ' ').replace(re, ' ').slice(1, -1);
      }
    }
    else
    {
      var i = -1, v, c; while((v = vs[++i]))
      {
        if((c = v.className))
          v.className = (' ' + c + ' ').replace(re, '').slice(1, -1);
      }  
    }

    return this;
  };
})();  

(function()
{
  _fnMap = {};
  
  $.fn.toggleClass = function(classes, addOrRemove)
  {
    var vs = this;
    
    if(!(classes > '') || vs.length == 0)
      return this;

    if(addOrRemove != null)
    {
      if(addOrRemove)
        return this._addClass(classes);
      else
        return this._removeClass(classes);
    }
    
    if(_fnMap[classes])
    {
      _fnMap[classes](vs);
      
      return this;
    }  
    
    if(classes.indexOf(' ') < 0)
    {
      /*
      if((c = v.className))
      {
        if(~(c = " " + c + " ").indexOf(' $1 '))
          v.className = c.replace(" $1 ", " ").slice(1, -1);
        else
          v.className += ' $1';
      }
      else
      {
        v.className = '$1'
      }
      */


      _fnMap[classes] = new Function(
        'vs',
        'var v,c,i=-1;while((v=vs[++i])){ ' +
          'if((c=v.className)){if(~(c=" "+c+" ").indexOf(" ' + classes + ' "))v.className=c.replace(" ' + classes + ' ", " ").slice(1, -1);else v.className+=" ' + classes + '";}else{v.className="' + classes + '"}}'
      );
    }
    else
    {
      /*
      if((c = v.className))
        c = ' ' + c + ' ';
      else 
        c = ' ';
      
      c = (c = v.className) ? ' ' + c + ' ' : ' ';
        
      if(~c.indexOf(' $1 '))
        c = c.replace(' $1 ', ' ');
      else 
        c += '$1 ';
      */  

      _fnMap[classes] = new Function(
        'vs',
        'var v,c,i=-1;while((v=vs[++i])){ c=(c=v.className)?" "+c+" ":" "; ' +
          classes.replace(/(\S+)/g, 'if(~c.indexOf(" $1 "))c=c.replace(" $1 ", " ");else c+="$1 ";') + 
          ' v.className = c.slice(1, -1); };'
      );
    }
    
    _fnMap[classes](vs);
    
    return this;
  };
})();