Re^2: Code clarification - use of map and $$

++AnomalousMonk: that helped (me, anyway; don't know about the OP). That was my first guess, but my initial experiments with the OP code didn't mesh. But I later saw that the print went to OUT, and forgot to redo a test to STDOUT. Thus I started thinking that it was a sub named END in a bout of horrible style. But I think you're right, it's an END block.

However, with this simplified code, I still only see the FIRST instance of the END block doing anything:

use strict;
use warnings;

$, = ",";
$\ = "\n";
$" = ";";

my %r = ( 0 => 0, 1 => 0, 2 => 0, 3 => 0 );

foreach (1..10) {
    my $x = $_ % 4;
    ++$r{$x};
    sub END { print __LINE__, "sub END block", $x, $r{$x} };
}

foreach(1 .. 10) { my $x = $_ % 4; print "$_ => $x => $r{$x}"};
print __LINE__, "END OF SCRIPT";
__END__
__OUTPUT__
1 => 1 => 3
2 => 2 => 3
3 => 3 => 2
4 => 0 => 2
5 => 1 => 3
6 => 2 => 3
7 => 3 => 2
8 => 0 => 2
9 => 1 => 3
10 => 2 => 3
17,END OF SCRIPT
13,sub END block,1,3
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Re^3: Code clarification - use of map and $$_ by AnomalousMonk (Archbishop) on Aug 09, 2016 at 15:28 UTC
... I still only see the FIRST instance of the END block doing anything ... From this I think you've already gotten the point, but anyway... There is only one instance of any given `END` block in a program: `c:\@Work\Perl\monks>perl -wMstrict -le "for my $str (qw(one two three)) { print qq{in for loop: '$str'}; END { print 'END block ONE'; } END { print 'END block TWO'; } END { print 'END block THREE'; } } " in for loop: 'one' in for loop: 'two' in for loop: 'three' END block THREE END block TWO END block ONE` [download] Give a man a fish: `<%-{-{-{-<`	[reply] [d/l] [select]
Re^3: Code clarification - use of map and $$_ by pryrt (Abbot) on Aug 09, 2016 at 15:21 UTC
Oops, re-reading AnomalousMonk's post and the OP, I was reminded that there was a loop inside the END block, and that does what was intended. use strict; use warnings; $, = ","; $\ = "\n"; $" = ";"; my %r = ( 0 => 0, 1 => 0, 2 => 0, 3 => 0 ); foreach (1..10) { my $x = $_ % 4; ++$r{$x}; sub END { $, = " => "; foreach my $k ( keys %r ) { print __LINE__, "sub END block with k", $k, $r{$k} } }; } foreach(1 .. 10) { my $x = $_ % 4; print "$_ => $x => $r{$x}"}; print __LINE__, "END OF SCRIPT"; __END__ __OUTPUT__ 1 => 1 => 3 2 => 2 => 3 3 => 3 => 2 4 => 0 => 2 5 => 1 => 3 6 => 2 => 3 7 => 3 => 2 8 => 0 => 2 9 => 1 => 3 10 => 2 => 3 22,END OF SCRIPT 16 => sub END block with k => 0 => 2 16 => sub END block with k => 1 => 3 16 => sub END block with k => 3 => 2 16 => sub END block with k => 2 => 3 [download]	[reply] [d/l]