Re: How do you create a tab delimited txt file from two files?

[almut]

in reply to How do you create a tab delimited txt file from two files?

Open the two files, then read a line from each file on every iteration:

while (my $col1 = <FILE1>) {
    chomp $col1;
    my $col2 = <FILE2>;
    print "$col1\t$col2";
}

[elef]

Ooooh, that's nice, I had no idea perl could do that. This is the sort of thing I was looking for.

One issue, though: it seems to choke if the two files don't have the same number of lines. I could just count the lines in each and pad the shorter file with as many \n as required before starting the loop, but there has to be a better solution than that. Any tips?

[Utilitarian]

while (my $col1 = <FILE1>) {
    chomp $col1;
    last unless (my $col2 = <FILE2>);
    print "$col1\t$col2";
}

the above will stop at the end of the shorter file

[elef]

Well, that's better than what the original script does, but I'd prefer to have the end of the longer file in the output as well, paired with empty "cells".

I.e. either

bla[tab]
bla[tab]
bla[tab]

or

[tab]bla
[tab]bla
[tab]bla

[moritz]

FWIW this can be written in Perl 6 very nicely:

$ perl6 -e 'for lines("a") Z lines("b") -> $a, $b { say "$a\t$b" }'

Where "a" and "b" are the names of the two files.

If the iteration should not stop after the second file is exhausted, we can pad the lines of the second file with an infinite number of empty strings:

$ perl6 -e 'for lines("a") Z lines("b"), '' xx * -> $a, $b { say "$a\t
+$b" }'

Works with Rakudo today.