Re: iterative foreach loop

[zarath]

Hello!

For the task you are describing I would use the following code:

use strict;
use warnings;
use autodie;

my $filename = 'Text2.txt';
my $count = 0;

open my $file,'<',$filename;

while (my $line = <$file>) {
    ++$count; # keep track of the number of lines
    printf "Line $count: $line";
}
close $file;

exit 0;

Note: when I need to open files for any reason, I tend to use autodie; so I can forget to add or die $!; to each open.

This code literally just opens your .txt-file and prints the following: "Line " number of the line ": " content of the line. It does not do much more.

But you did mention you would like to store the lines into an array. For later use perhaps?

In this case it would become this code:

use strict;
use warnings;
use autodie;

my $filename = 'Text2.txt';
my $count = 0;
my @lines; # declare the array to be used for storing

open my $file,'<',$filename;

while (my $line = <$file>) {
    ++$count; # keep track of the number of lines
    push (@lines,'Line ',$count,': ',$line); # fill the initially empt
+y array with the needed data
}
close $file; # do not need this anymore

for my $newline (@lines) {
    printf $newline; # print the contents of the filled array
}

exit 0;

The result of both codes is the same, but in the second version all lines (with linecount) are stored inside the array @lines so you can easily use it for whatever you want after the while-block is closed without needing to read from $file again. This would be more difficult in the first version I think.

You can of course format the lines of your array however you like it by editing the push: push (@array,'fill','this','however','you','want');

Hope this is helpful.

[hippo]

for my $newline (@lines) {
    printf $newline; # print the contents of the filled array
}

This seems confusingly verbose to me. Why not simply

print @lines;

There's no need for printf, for an explicit loop or for a lexical scalar. TIMTOWTDI, but there is clarity in simplicity.

[zarath]

Good points, thanks for that!

I think I picked up some bad habits by learning Perl mainly from some old scripts I've come across at work.

Starting to think the guy who wrote them shouldn't have...