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Subject: Re: [boost] [outcome] How to drop the formal empty state
From: Niall Douglas (s_sourceforge_at_[hidden])
Date: 2017-05-26 23:59:29

>> As you'll note, the first possible state (empty) tends to be chosen by
>> the compiler as the most likely. That implies a 20 cycle branch
>> misprediction cost for each of the valued or errored states. So they
>> are equally costly, which is intentional.
> Wait a minute. Are you saying that you consider the fact that valued and
> errored are equally slow a feature, instead of one of them being fast?
> How is that a good thing? Of course empty should be the least likely -
> it _is_ the least likely.

As I've mentioned several times already in other threads, that was a
deliberate and intentional design choice for outcome/result. Predictable
latency throughout.


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