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From: Ville Voutilainen <ville.voutilainen@gmail.com>
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Subject: Re: optional<T>, one more value or two states
Date: Mon, 28 Jan 2013 00:16:55 +0200
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On 27 January 2013 23:48, Nicol Bolas <jmckesson@gmail.com> wrote:
> It's not a "problem" with the constructor. The constructor is doing exactly
> what it is supposed to. The problem is with the expectation that
> pointer-like things have reference semantics.
> Optional is neither a container nor a pointer. It is its own type of thing,
> and it should have whatever is appropriate for users of that type. We don't
> want it to look too much like a pointer, lest users get the wrong idea. And
> we don't want it to look too much like a container, for the same reason.

I get no wrong ideas about optional or value_ptr or shared_ptr or unique_ptr,
despite their having operator*. I don't expect them to have pure reference
semantics. I have used various kinds of pointers as a substitute for having
a real optional, so in that sense I have no problem with optional being
somewhat pointer-like either.

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