I'm afraid I didn't make my point clear. It wasn't about supporting BOOST_NO_EXCEPTIONS (which I'd like not to --it would require in any case a re-examination of the code, as I didn't design it with that in mind). It was to discuss what type of exception(s) we want to throw and what additional info, if any, we want to add to exception objects. Maybe Boost.Date-Time already has a well thought-out solution.
Then I have no clue for this :) I'm not sure we are understanding each other. The main advantage of my
solution is that it doesn't logically imply/require any usage of a "time point". That means: if you measure while someone (or some program/service) adjusts the system clock, or a DST switch happens, you are *not* affected.
We are, it's just I copy pasted too much for my example. My point was mostly for the clock_device and the time_duration_type that should be able as typedefs.
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void resume(); // gps - what if you call twice pause, twice resume consecutively?? // bool is_running() const // gps - add this?? // gps: I see no point in having clear_elapsed()
I think calling twice pause or resume should have no effect.
Maybe.
It's not a media player where the interface tries to be friendly and pressing pause toggles play/pause, it's a timer where pause means pause no ?
Not doing so is
too error prone imho. is_running() sounds like good idea tho I can't really think of a use for it so maybe not if that means having to add a data member to implement it.
Basically you are saying you are in doubt. I was too, hence my question (incidentally: what's your concern with an additional data member??).
I'm just explaining why it's a doubt yes. The concern about an additional data member is silly but it's something about if the feature is never used and the object gets bigger then it's just lose-lose. But after more thinking is_running also helps the implementation clarity so I think we'd add it.
I think reset() was good, why don't you see a point for it ? If you want to
time two consequent things individually and use the same object ?
restart()?
Restarts resets and starts again, it's two actions. You don't provide the 1st one.
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template <typename D> void elapsed_timer<D>::start() // may throw { restart(); // this is just the same as restart(); // maybe we can come up with a common name -gps }
I think calling start() twice should not reset it, I think restart should call reset() then start().
Honestly, did you really look at my code? Looks like you keep thinking in terms of yours. I had no concept of reset() at all.
Maybe I wasn't clear: I said your interface lacks the reset() concept, and that restart() should be reset() then start().
Again, I think pause should pause if not already paused, otherwise do
nothing, like the implementation I uploaded based on Jeff's design.
I see. But the point is: if the user code happens to call pause() twice without intervening restarts, is that a sign of a logical error? It's similar to set a pointer to null after a delete, to ensure a double deletion is harmless. It may make you feel safer, but in practice it hides programming errors by eating their immediate ill effects.
For me it's not an error. If the user wants to do cout.set_precision(23); cout.set_precision(23); it's his problem :) What we could do is return a bool that'd tell pause() success tho.
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// Specific Clock Devices // gps - should this be copyable?
Why not ?
It's a choice, and I annotated it to make sure I gave it another thought at the end of the work.
It's usually a choice driven by the fact that copying it might be harfmul or imply extra design decisions (resources etc) but here I don't see why it wouldn't be.
I also think your interface lacks the hability to set the initial time
offset, which could be usefull in some situations.
Care to explain?
For the "I want to create a timer that starts with 100 second elapsed already" kindof requests. Philippe