argfunc = function() {
      if (arguments.length === 1 && Array.isArray(arguments[0])) {
        list = list.concat(arguments[0]);
      } else {
        list = list.concat([].slice.call(arguments));
      }
    }
Create an argument list

Returns a function that adds new arguments to the list.
It also has the following methods:
- clear() empties the argument list
- get() returns the argument list
- find(arg, count) finds 'arg' in the list and return the following 'count' items, or undefined if not found
- remove(arg, count) remove 'arg' in the list as well as the following 'count' items

@private