The problem is that interally, "$i\n" becomes $i . "\n" - which demonstrates why the problem occurs. You have to interpolate the value beforehand: 
for (my $i = 0; $i<3; $i++) {
    my $str = "$i\n";
    push @d, sub { print $str };
}

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However, that will not work correctly: 
0
1
2
Oops. You meant 
for (my $i = 1; $i<=3; $i++) {
    my $str = "$i\n";
    push @d, sub { print $str };
}

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Because of this sort of problems, you should use the for(LIST) form. 
for my $i (1..3) {
    my $str = "$i\n";
    push @d, sub { print $str };
}

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That eliminates an entire class of mistakes known as "fencepost errors", where the loop limit condition is fudged, usually resulting in one-off errors (one iteration too many or too few).

Makeshifts last the longest.

In reply to Re: evaluation strategy of perl by Aristotle
in thread evaluation strategy of perl by mayaTheCat

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