Simple code for adding and deleting class by native js

Example code:

function hasClass( elements,cName ){ 
  return !!elements.className.match( new RegExp( "(\\s|^)" + cName + "(\\s|$)") ); 
}; 
function addClass( elements,cName ){ 
  if( !hasClass( elements,cName ) ){ 
    elements.className += " " + cName; 
  }; 
}; 
function removeClass( elements,cName ){ 
  if( hasClass( elements,cName ) ){ 
    elements.className = elements.className.replace( new RegExp( "(\\s|^)" + cName + "(\\s|$)" ), " " );
  }; 
};