If you don't need the list, you can of course use the match itself as for's expression.

I thought so, too :( 

$ perl -e'$x="1 2 3 4 5 5 5 5 5 5"; $counts[$1]++ for $x=~/(\d)/g; pri
+nt "$_ $c
ounts[$_]\n" foreach (0..$#counts)'
0
1
2
3
4
5 10

[download]
How's that for a wierd problem?

Even stranger, if you s/for/while/: 

$ perl -e'$x="1 2 3 4 5 5 5 5 5 5"; $counts[$1]++ while $x=~/(\d)/g; p
+rint "$_
$counts[$_]\n" foreach (0..$#counts)'
0
1 1
2 1
3 1
4 1
5 6

[download]
This is with 5.6.1.

Ignore me; it makes sense that $1 would be the last value with a for loop. $_ works fine. 

$ perl -e'$x="1 2 3 4 5 5 5 5 5 5"; $counts[$_]++ for $x=~/(\d)/g; pri
+nt "$_ $counts[$_]\n" foreach (0..$#counts)'
0
1 1
2 1
3 1
4 1
5 6

[download]
With a while, you have to use $1; that's confused me. 
$ perl -e'$x="1 2 3 4 5 5 5 5 5 5"; $counts[$1]++ while $x=~/(\d)/g; p
+rint "$_ $counts[$_]\n" foreach (0..$#counts)'
0
1 1
2 1
3 1
4 1
5 6

[download]

--
Mike

In reply to Watch $1 vs. $_ in for loops... by RMGir
in thread Regex: plucking numbers from a large string by Baz

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