rconsole.js
function defined () {
  for (var i=0; i<arguments.length; i++)
    if (typeof arguments[i] !== 'undefined') 
      return arguments[i]
}
function defined () {
  for (var i=0; i<arguments.length; i++)
    if (typeof arguments[i] !== 'undefined') 
      return arguments[i]
}
function defined ( ) { for ( var i = 0 ; i < arguments . length ; i ++ ) if ( typeof arguments [ i ] !== 'undefined' ) return arguments [ i ] }
Return the first argument that is not undefined

@api private
Return the first argument that is not undefined