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Subject: Re: optional<T>, one more value or two states
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On Thu, Jan 24, 2013 at 6:15 AM, Zhihao Yuan <lichray@gmail.com> wrote:
> On Thu, Jan 24, 2013 at 8:05 AM, Chris Jefferson
> <chris@bubblescope.net> wrote:> True. But looking at the boost mailing
> list and bug reports, there does not
>> I have written quite a lot of code with boost::optional, it is very common
>> to make an optional<T> from a T, in 'return' statements for example. Having
>> to add an explicit cast to all of those would annoy me.
>
> Jeffery proposed a convert() utility to solve a problem like this:
>
> http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2013/n3521.html

That proposal is for types that have a good reason to make their
conversions explicit. optional<T> has good reasons to make its
conversion implicit, and if convert() is adopted, those reasons
wouldn't go away.

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