Perl6: is there a phaser that runs only when you fall out of a loop? - raku

Question

Take this sample code:
#!/usr/bin/env perl6
use v6.c;
ROLL:
for 1..10 -> $r {
given (1..6).roll {
when 6 {
say "Roll $r: you win!";
last ROLL;
}
default {
say "Roll $r: sorry...";
}
}
LAST {
say "You either won or lost - this runs either way";
}
}
I'd like to be able to distinguish falling out of the loop from explicitly saying last.
Ideally, there'd be a phaser for this, but as far as I can find, there is only LAST which runs in either case.
Is there an elegant way to do this? (Elegant, so without adding a $won variable.)

Answer 1

We're dealing with Perl, so There's More Than One Way To Do It; one of them is using the topic variable $_ to keep the value so we can easily match against it repeatedly:
constant N = 5;
for flat (1..6).roll xx * Z 1..N -> $_, $n {
print "roll $n: $_ ";
when 6 {
put "(won)";
last;
}
default {
put "(lost)";
}
LAST {
print "result: ";
when 6 { put "winner :)" }
default { put "loser :(" }
}
}

Answer 2

Here's another way to do it. Elegant? I think reasonably so. I wish there were a separate phaser for this, though.
#!/usr/bin/env perl6
use v6.c;
constant MAX_ROLLS = 10;
ROLL:
for 1..MAX_ROLLS+1 -> $r {
last ROLL if $r > MAX_ROLLS;
given (1..6).roll {
when 6 {
say "Roll $r: you win!";
last ROLL;
}
default {
say "Roll $r: sorry...";
}
}
LAST {
say "You lost, better luck next time!" if $r > MAX_ROLLS;
}
}