Re: [boost] [outcome] outcome without empty state?

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When it comes to converting from `prepare_expected` to `expected`, you have plenty of choices: require manual conversion, narrow-contract to be checked, a defensive if and throw... I am just not sure if performance can be negatively impacted with this.

I originally considered this design for Outcome's API.

I ended up rejecting it because it's superfluous if you have correctly designed your expected/outcome/whatever in the first place.

What does "correctly" mean here?

Well, indeed :) Where I'm aiming, as you'll see in the summary design document I'll post shortly, is that the implicit conversion semantics will provide the ability to use a less representative variety to construct things, but return into a more representative variety. Niall -- ned Productions Limited Consulting http://www.nedproductions.biz/ http://ie.linkedin.com/in/nialldouglas/