On Wednesday, 6 August 2014 at 08:25:38 UTC, Walter Bright wrote:
Thank you for the well thought out response.
I responded to the equivalent design proposal several times already, with detailed answers. This one is shorter, but the essential aspects are there. I know those negative aspects came across because they are addressed with your counter:
I was not trying to attack you, but rather inform you. I think that is all I want to say on the subject so I am going to stop talking about it.
1. it's long with an unappealing hackish look
I find this a positive, the proposed assert has quite dangerous implications, having a slightly "hackish" look will serve to discourage using it when it is not obviously needed.
2. it follows in the C++ tradition of the best practice being the long ugly way, and the deprecated practice is the straightforward way (see arrays in C++)
That is implying that the best practice is your version of assert. As it can introduce undefined behavior, I find it hard to believe.
3. users will be faced with two kinds of asserts, with a subtle difference that is hard to explain, hard to remember which is which, and will most likely use inappropriately
This is why I think it would be best added as an annotation on assert. People who don't care enough to look up what the extra annotation does will just use assert by itself and have no risk of undefined behavior and it will behave as expected(similar to how it behaves in other languages).
4. everyone who wants faster assert optimizations will have to rewrite their (possibly extensive) use of asserts that we'd told them was best practice. I know I'd be unhappy about having to do such to my D code.
This is a fare point but it would happen the same either way. If some one used assert expecting it to act like the C assert and found out it did not any more, they would be forced to go through though there code and change all the asserts. As this is a change, I am inclined to say we should favor the old version and not force users of the old version to update.
This is not about my feelings, other than my desire to find the best design based on a number of tradeoffs.
I was just trying to say that it is a possibility that should not be forgotten, I think I may have said it in a harsher way than I meant to, I apologize. The annotated assert was my attempt at a possible compromise.
