Hello iThunder,

As GrandFather says, you should put text into paragraphs using <p> ... </p> tags, and you should enclose code and data in <code> ... </code> tags. I also moved your post from Perl Monks Discussion to Seekers of Perl Wisdom.

Regarding the flip-flop operator (viz., .. in scalar context), you are confusing line numbers with sequence numbers. Actually, the flip-flop operator evaluates to a boolean value, i.e., either true or false. When the operator evaluates to true, Perl, as a convenience, returns “true” in the form of a sequence number. Consider:

use strict;
use warnings;

my $p;

while (<DATA>)
{
    chomp;

    if ($p = 3 .. 5)
    {
        print "$_: \$. is $.: p is $p\n";
    }
}

__DATA__
line 1
line 2
line 3
line 4
line 5
line 6
line 7

[download]

Output:

14:00 >perl 1020_SoPW.pl
line 3: $. is 3: p is 1
line 4: $. is 4: p is 2
line 5: $. is 5: p is 3E0

14:00 >

[download]

Note that the string E0 is appended to the final true value: this “gives you something to search for if you want to exclude the endpoint.” — perlop#Range-Operators.

Update: Added printout of $..

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re: flip flop operator and if statement by Athanasius
in thread flip flop operator and if statement by iThunder

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