Carl Mäsak wrote:
Andy (>):
P6 treats the key/value as an anonymous 'pair' object so @ranking is an
list of pairs. That's why:
say @ranking.pop.fmt("$m Medal: %s, %s")
or, less succinctly:
say (pop @ranking).fmt("$m Medal: %s, %s");
works - the pair object, popped off into the 'printf' like 'fmt' method
(akin to:
my $skater_pair = pop @ranking;
printf("$m Medal: %s, %s\n", $skater_pair);
or, longer:
printf("$m Medal: %s, %s\n", $skater_pair.key, $skater_pair.value);
) devolves into a list (key, value) which fills the 2 '%s' fields.
hashes, then, are lists of pairs, indexed by their 'key' attribute.
I think, anyway.
You are right about everything but the 'devolves into a list' part.
Look at S29:1599, and you'll note that one of the four flavours of
.fmt method lives in the Pair class. No devolving required.
Because of this, the .fmt call is not equivalent to the version of
printf taking a pair:
printf("$m Medal: %s, %s\n", $skater_pair);
In fact, this line throws a "Null PMC access in get_string()" in
Rakudo, which bug I just reported.
Thanks,
// Carl
Actually Andy had 'printf("...",$skater_pair.key, $skater_pair.value);'
which works.
However, I came across one thing in solution #3 that I posted yesterday.
$pair.fmt("%s %s") is nice, but it doesnt allow for any action on either
value or key before printing (I wanted to print the value as a
percentage), and this had to be done in a printf statement. In fact the
printf statement was the longest and ugliest statement in the program.
Richard
