TimeOfDay's roll function refers to an add method which would increment or decrement the next greater unit of time when it wraps a unit of time. This method seems to be absent, while DateTime has it.

Actually I see DateTime's method is days and months only, why aren't hours, minutes and seconds available?

On 09/20/2012 09:02 AM, ixid wrote:
> TimeOfDay's roll function refers to an add method

I see how "The difference between rolling and adding ..." implies that there is also an add() function just like there is a roll() function. In fact, adding is handled simply by operator overloading. You can add Duration objects:

  t += duration;
  auto newTime = t + duration;

Ali

On Thursday, September 20, 2012 18:02:04 ixid wrote:
> TimeOfDay's roll function refers to an add method which would increment or decrement the next greater unit of time when it wraps a unit of time. This method seems to be absent, while DateTime has it.

Create a Duration and use +. e.g.

auto t = timeOfDay + dur!"seconds"(12);

Maybe rolling's docs aren't clear enough, but they never actually mention an add function. They mention adding but not an add function.

An add method exists on SysTime, DateTime, and Date only because you can't have a Duration of anything greater than weeks, because you can't convert between months and smaller units without a specific date. So, a separate function is needed. Everything else uses the arithmetic operators.

- Jonathan M Davis