in reply to Issue with unless statement with two conditions acting on two lines

use strict;
use warnings;

my $saw_an_s = 0;
while (my $current_line = <DATA>) {
    next if ($saw_an_s and $current_line =~ /^s/);
    $saw_an_s = $current_line =~ /^s/ ? 1 : 0;
    print $current_line;
}
__DATA__
s 1
s 2
s 3
a

a foo
s 4
s 5
s 6
a bar

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Just keep a flag rather than store the whole of the previous line each time - much simpler (to my mind). HTH.

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Re^2: Issue with unless statement with two conditions acting on two lines
by rjc33 (Sexton) on Jan 08, 2016 at 16:07 UTC
    Thanks for the suggestion, I'll try this in the future!
[reply]

      Note that hippo's approach above also prints the first line without further effort.

      Give a man a fish:  <%-{-{-{-<

[reply]
[d/l]

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