So, after all our discussions, my thinking regarding alternate blocks for
loops is now running like this:
1. It would definitely be useful to be able to catch the failure of a
block to iterate.
2. This ability should be available for all three types of block: C<while>,
C<for>, and C<loop>.
3. The "obvious" syntax:
while condition() {
...
}
else {
...
}
is fraught with difficulty because C<else> is already so closely
bound to C<if> in the community consciousness.
4. Using C<else> also encourages the expectation of C<elsif>, C<elswhile>,
C<elsunless>, C<elsinore>, etc. But I don't believe the language can
comfortably bear the weight of such expectations. Or such keywords.
5. My preferred option would be to restrict the "alternative block" to
only being a simple block (i.e. no cascading), and to introduce it
with some other keyword.
6. C<otherwise> would seem to fit the bill rather nicely.
So, I guess if Larry were to ask my opinion, I'd suggest that we allow:
while condition() {
...
}
otherwise {
...
}
and:
for @list -> $next {
...
}
otherwise {
...
}
and:
loop ($i=0; i<$max; i+=2) {
...
}
otherwise {
...
}
I now confidently await Larry's coming up with an entirely different solution ;-)
Damian
