Are you sure the first one works and the second doesn't? If I add strictures to the top of your script and supply @_lines the following error is generated:

Global symbol "$_line" requires explicit package name at noname1.pl li
+ne 10.
Execution of noname1.pl aborted due to compilation errors.

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Line 10 is the line my $templine = $_line; in the first loop. If I remove strictures but add (1) and (2) as appropriate to the conditional print statements in the two loops I get:

ABC = the line (2)

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so maybe all your problem is is that you aren't using strictures and you have an old fashioned "typo in a variable name" error? Oh, the test code I used was:

#use strict;
#use warnings;

my @_lines = <<LINES;
ABC in the first line
but not the second
LINES

foreach my $line (@_lines) {
    my $templine = $_line;
    print "$templine";
    # or  print "$line";
    if ($templine =~ /(ABC)/) {print "$1 = the line (1)";}
}

foreach my $_line (@_lines) {
    my $templine = $_line;
    ############   print "$templine";
    ############   # or  print "$line";
    if ($templine =~ /(ABC)/) {print "$1 = the line (2)";}
}

[download]

Uncomment the strictures to get helpful errors and warnings.

True laziness is hard work

In reply to Re: Printing the variable makes the next match code work. Why? by GrandFather
in thread Printing the variable makes the next match code work. Why? by scaryfast

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