Hi, I hope my questions aren't trivial, I can't figure out why replacing the default $_ with an arbitrary variable gives different results, my questions follow, hope you can help, thanks :)

I'd also like to know why if I specify even-numbered elements, nothing returns, eg. if I type

print $fields[0], "\r";

on line 12 in my script, I get nothing. I've found that any even-numbered element specified on line 12 gives me nothing, it's odd, I thought the 0th element would be 'Baw', the 1st element would be 'Vao' and so on. The pipe is discarded by perl, so I don't understand why the even-numbered elements are 'skipped', so to print 'Baw', I type

print $fields[1], "\r"

and to print 'Vao', I type

print $fields[3], "\r"

1. If I use $in on Lines 6 - 8 and print any elements, the entire lines of the file are returned without being processed (with pipes included). I thought I could substitute $_ with any variable. Why won't it work here?

2. If I use $_ on these lines instead, then I get good results (eg. I get the element specified on Line 12.

3. If I UnComment Lines 9 - 11, a '1' is returned for each record/line between the last 2 elements from the file. Why is that?

1 #!/usr/bin/perl -w
2 use strict;
3 
4 open my $datfh, '<', 'C:\begperl\my scripts\cdata.txt' or die "Could
+n't open file: $!\n";
5 
6 foreach my $_ (<$datfh>) {
7     my @fields = (map { s/^\s+//; s/\s+$//, $_ }    # eliminates irr
+elevant spaces
8     split /\|/, $_);
9 #        for my $i (0 .. $#fields) {
10 #        print $fields[$i], "\n" unless $fields[$i] =~ /\r|\n/;
11 #        }
12     print $fields[1], "\r";
13 }
14 close $datfh;

[download]

My File's data (for testing):

Baw|Vao|111 Noa St||NewYork|NY|10012|2123456789|123456789

Vca|Wxr|384 Mkl Ln|Xillo|Crrnt Stt|CT|05506|1015567781|1015567782

Uaa|Kvbr|805 Test Rd|Zero|This St|MN|17205|3018757203|3012986736

Caa|Lvbr|905 Test Rd|Bero|That St|MD|12705|3028887203|3028886736

Eaa|Pvbr|311 Zest Rd|Tero|My St|MI|12505|3018757203|3012986736

In reply to variable mystery by jeah

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