use Pointy::Counter;

my $i = counter;
while ($i --> 10)
{
  print "Counter is $i\n";
}

[download]

This achieved via some fairly basic (albeit unintuitive) use of overloading. See https://metacpan.org/release/TOBYINK/Pointy-Counter-0.001.

I really need to investigate here to see how feasible it would be to achieve syntax like this:

use Pointy::Counter;

while (ctr $i --> 10)
{
  print "Counter is $i\n";
}

[download]

Replies are listed 'Best First'.
Re: pointy counters
by choroba (Cardinal) on Dec 22, 2011 at 09:32 UTC
    What about the inverted arrow? :-) 
    perl -E '$from = 0; $to = 10; say $to while $to    --> $from'
perl -E '$from = 0; $to = 10; say $to while $from <--  $to'

    [download]
[reply]
[d/l]
Re: pointy counters
by keszler (Priest) on Dec 20, 2011 at 23:35 UTC
[reply]
Re: pointy counters
by jffry (Hermit) on Dec 20, 2011 at 23:38 UTC

    This is kind of neato, I suppose, but I'm having trouble figuring out why. What's wrong with a for loop and a range operator?

    for my $i (1..10) {
    print "i = $i\n";
}

    [download]
[reply]
[d/l]
      Well, duh. The range operator isn't even nearly pointy enough!
[reply]
      That is merely point-ish, not pointy :)
[reply]
Re: pointy counters
by choroba (Cardinal) on Dec 21, 2011 at 08:39 UTC
    This works without any module: 
    my $c = 10;
print "$c\n" while $c --> 0;

    [download]
[reply]
[d/l]

      Yeah, counting backwards works without needing Pointy::Counter. That's why Pointy::Counter only offers support for counting forwards.

[reply]
[d/l]
[select]

        I do not even understand the topic nor the syntax 
        perl -e "my $c = 10; print qq!$c\n! while $c --> 0;"

        [download]
        but I see that also 
        perl -e "my $c = 10; print qq!$c\n! while $c ++> 0 && $c < 100;"

        [download]
        runs fine.. BUT what a notation is this --> or ++> ?
        there are no rules, there are no thumbs..
[reply]
[d/l]
[select]

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