code: function(input, shallow, output) 
  	{
  		if (shallow && conbo.every(input, conbo.isArray)) 
  		{
  			return concat.apply(output, input);
  		}
  		
  		forEach(input, function(value) 
  		{
  			if (conbo.isArray(value) || conbo.isArguments(value)) 
  			{
  				shallow ? push.apply(output, value) : flatten(value, shallow, output);
  			}
  			else 
  			{
  				output.push(value);
  			}
  		});
  		
  		return output;
  	}
docs: Internal implementation of a recursive `flatten` function.
  @private