All you need is another pair of curlies. And it will actually work correctly, unlike the state variables.

{ my $i;
foreach (@array) {
    do_something_with($item, $i++);
}}
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BTW, you should NOT use

printf " %2d.  '$color'\n", $idx;
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printf " %2d.  '%s'\n", $idx, $color;
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Yes, you're right. That "fly in the ointment" just now occurred to me, and I was going to update my post to point this out. It unfortunately makes many applications (such as tracking line numbers from a file) useless, except for the very first time.  Rats.

It brings me back to a previous thought -- I wonder what it would take to implement a special Perl variable to track the loop count? For example, $* is now deprecated; perhaps it could be "reused" for something like this?

Anyway, thank you for finding my flaw early on.

---

s''(q.S:$/9=(T1';s;(..)(..);$..=substr+crypt($1,$2),2,3;eg;print$..$/

The D language has a nice pragmatic variation on the foreach loop.

Written this way, c takes on each of the values in the array a in turn:

char[] a;
...
foreach (char c; a) {
...
}
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Written this way, the same thing happens, but also i takes on the index of the value also:

char[] a;
...
foreach (int i, char c; a)
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I don't think there's any possibility of getting that into 5.12 (nor even Perl 6 at this late stage), but it one of those few features of other languages I miss when I'm writing Perl.

perl6 already has the kv thingy:

for @x.kv -> $index, $value {
  say $index, ' ', $value
}
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(tested with rakudo, it works)
[]s, HTH, Massa (κς,πμ,πλ)

Great! I vaguely remember seeing stuff about that, but my memory confined its use to hashes.

---

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

"Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."

Python has enumerate for this. For example:

for i, item in enumerate(array):
    do_something_with(item, i)
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The nearest thing I can find to that in Perl is the List::MoreUtils pairwise function, something like:

my @idx = 0 .. $#array;
pairwise { do_something_with($b, $a) } @idx, @array;
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or perhaps the CPAN Array::Each::Override module.

You can achieve something similar without modules a couple of ways:

@a = 'A'..'J'; 
for my $r ( map { k=> $_, v=> $a[ $_ ] }, 0 .. $#a ) { 
    print "@{ $r }{ k, v }\n" 
}

0 A
1 B
2 C
3 D
4 E
5 F
6 G
7 H
8 I
9 J
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Or

@a = 'A'..'J'; 
for my $r ( map [ $_, $a[ $_ ] ], 0 .. $#a ) { 
    print "$r->[0]:$r->[1]\n" 
}
0:A
1:B
2:C
3:D
4:E
5:F
6:G
7:H
8:I
9:J
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---

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

"Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."

  my $transformed=$original;
  $transformed =~ s/.../.../;
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Then I discovered that I could keep the original and the transformed value by doing this one liner:

(my $transformed=$original) =~ s/.../.../;
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Best, beth

... it wastes time, and extra space, to go back and modify the foreach loop to the equivalent for loop (ignoring for a moment the synonymity of foreach and for):

for (my $i = 0; $i < @array; $i++) {
    my $item  = $array[$i];
    do_something_with($item, $i);
}
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Even a shorter idiom takes an extra line, and isn't quite as "clean" (imo), as the $i has to be defined outside of the loop:

my $i;
foreach (@array) {
    do_something_with($item, $i++);
}
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I think the following is just as simple as using state or any other variation, and doesn't require any more lines of code than your original:

for my $i (0..$#array) {
    do_something_with($array[$i], $i);
}
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use feature ":5.10";
my %hash = map { $_ => state $i++ } qw(red blue green yellow black whi
+te purple brown orange gray);

for (1..2) {
    while (($k,$v) = each %hash) {
        do_something_with($k, $v);
    }
}
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for (1..2) {
    while (($k,$v) = each %hash) {
        do_something_with($k, $v);
    }
}
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Talking about state, you know your code may not do what you expect it to do, don't you? 'each' is an iterator which keeps state on the hash itself. Which means that if the loop exits prematurely (which could even happen in this code if do_something_with contains a 'last') the next time around, it will iterate over the entire hash.

You may want to develop the habit to write keys %hash; in void or scalar context right before each each. (It's not an easy habit to get used to - each isn't common enough for that - half of the time, I forget it my own good advice).

foreach (@array) {
    do_something_with($item, state i++);
}
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my $i;
foreach (@array) {
    do_something_with($item, $i++);
}
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And since 'state' is something I rarely use (ok never) you can bet I'll be looking it up in the docs every time I see it to be sure of exactly what it's doing. It's sometimes annoying that there's no magic variable to get an index in a foreach, but I think you've sacrificed readability (and portability) for the sake of a single line of convenience?

How do you think the other veterans felt about this crazy new my keyword that they had to lookup everytime they encountered it when my was first introduced?! </joke>

I find your first bit of code cleaner--I always hate taking up an extra line above my foreach loops.

And you didn't even know bears could type.

my %hash;
my $count = 0;
foreach my $key qw(red blue green yellow black 
                                white purple brown orange gray){
   $hash{$key}{'index'} = $count;
   $hash{$key}{'state'} = 0;
   $count ++; 
}
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