I try to avoid stuff like $tmp[0] because you need a comment to describe what the heck the 0th field actually means! I used an array slice to move the indexing into the split so that I could assign this first column a scalar name. You should use terminology appropriate for your application. I didn't see the need for chomp, only to add a "\n" back in. The split will remove any \n if there is just one token on the line. Also, I personally wouldn't put multiple statements on the same line. Perl doesn't care, but people do.
I would do something different if this involved reading chunks of more than 2 lines. But this specific case, I find the below adequate.
Update: Oh, I usually put the numbering on the left. I know how big that column is going to get. Done the other way around, a long token will screwup your nice printout. You didn't specify what is to happen with an odd number of line - it could be "silent ignore" approach above is not what you want - but I couldn't tell.use strict; use warnings; my $cnt=1; while (defined (my $first = <DATA>) and defined (my $second = <DATA>) +) { my $name1 = (split /\s+/, $first)[0] // last; # handle trailing my $name2 = (split /\s+/, $second)[0] // last; # potential "\n" bl +ank lines print "$cnt\t$first"; if ($name1 ne $name2) { $cnt++; } print "$cnt\t$second"; } =prints 1 one 1 one 1 two 1 two 1 three 1 three 1 three 2 four note: same result with or without the trailing blank line =cut __DATA__ one one two two three three three four Odd line here followed by a blank line if you want
In reply to Re: Dealing with nextline of a file
by Marshall
in thread Dealing with nextline of a file
by jnarayan81
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