On 02/01/18 16:40, Jonathan Müller via Boost wrote:
On 01.02.2018 14:32, Andrey Semashev via Boost wrote:
On 02/01/18 15:03, Jonathan Müller via Boost wrote:
And accessing the value on an optional without checking it should always be a red flag and not just written "naturally" (That's why operator-> for optional is a mistake IMO).
I disagree. The necessity to write ".value()" on every access to `a` is an overhead, both in user's effort and runtime performance. This, actually, illustrates my point.
With my proposal, `value()` would be the unchecked (i.e. debug checked) access, so it has no effort on runtime performance.
If your `value()` is unchecked then I really don't understand how writing `a.value().foo()` would be less error prone than the current `a->foo()` without a prior check.
Yes, it is less convenient than exceptions, that's why you should still prefer exceptions without more language support for optionals and expected objects.
But I don't think it is more error prone than exceptions, which is the point I'm trying to make.
The more code you have to type, the more places where you can make a mistake. My point is that since with exceptions you don't need to type any code to test for errors, except where you actually do, it is less error prone.