Andrei Alexandrescu wrote:
Don wrote:
Andrei Alexandrescu wrote:
Chad J wrote:
So, switch-case statements are a frequent source of nasty bugs. Fixing
them (well) requires breaking backwards compatibility.
Any chance this will happen for D2?
(This is intended as more of a reminder and simple curiosity than a
discussion.)
Walter's answer to that has put me to silence for good. "But I use
fall-through all the time!" I then knew the feature will never make it.
It's actually not something I care about at all. But I think Walter's
wrong about his coding style. And looking at how rarely it's actually
used by someone who thinks he uses it a lot, convinces me that
intentional use of fall-through is much less common than bugs
introduced by leaving out a break statement.
An interesting result.
But I'd much rather change Walter's mind about opPow() or the
meta.compiles(XXX) proposal.
Don <---------- genius
Nah, I just know how Walter's mind works. It takes one to know one...
I frequently use fall-through myself, but having looked at this sample,
I bet I don't use it nearly as much as I thought: again, "frequently"
probably means "about 1% of the time". But I *know* I've had bugs from
leaving out 'break'.
I understand that you're more interested about the issues that preoccupy
you (and incidentally me) the most, but "switch" is a day-to-day
programming (and programmer's) workhorse, so a change there might have a
wider (and hopefully more positive) impact.
I should have said "immutable array literals" instead.
>>> I wish very much that a transferring control flow statement (break,
>>> return, goto etc.) is required at the end of each case. Then, the
>>> rare case when you want to break through is easy to implement as goto
>>> case xxx; and all is good.
Requiring 'goto' to implement fall-through would run into the prejudice
against 'goto'. It's necessary to persuade managers that "goto case
XXX;" isn't a bad, evil goto that eats babies. I have no idea if that's
difficult or not. Otherwise, I think it's a superb solution.
(providing that empty fall-through case statements remain valid;
disallowing them would be really annoying).
