Perl Regex not matching - regex

Question

I'm trying to match lines from a file and extract a certain part.
My Regex works with all online testers I could find but not with my perl.
I'm on version v5.10.0 and cannot update.
The regex looks like this:
sub parse_bl_line {
if ($_[0] =~ m/^copy\s+.*?\s+(.*?\_.*)/) {
return $1;
} else {
log_msg("Line discarded: $_[0]", 4);
return "0";
}
}
A couple lines of test data which should match (only the last matches):
#bl_lines = (
"copy xxxxxx_/cpu b_relCAP_R3.0-1_INT5_xxxxx_cpu_p1",
"copy xxxxxxxx_/va_xxx_parameters b_relCAP_R3.0-1_INT5_xxxxx_va_xxx_parameters_p1",
"copy xxxxxxxx_/xxxxxxx_view.tcl b_relCAP_R3.0-1_INT5_xxxxxx_view.tcl_p0",
"copy xxxxx_/xxxxxarchivetool.jar b_relEARLY_DROP1_xxxxxarchivetool.jar_xx");
And calling the function:
foreach(#bl_lines) {
$file=parse_bl_line($_);
if ($file !~ "0") {
log_msg("Line accepted: $_", 4);
log_msg("File extracted: $file", 4);
}else {
log_msg("Line rejected: $_", 2);
}
}
I'm trying to match the last part e.g.
b_relEARLY_DROP1_xxxxxarchivetool.jar_xx
Output looks the following:
20120726 13:15:34 - [XXX] ERROR: Line rejected: copy xxxxxx_/cpu b_relCAP_R3.0-1_INT5_xxxxx_cpu_p1
20120726 13:15:34 - [XXX] ERROR: Line rejected: copy xxxxxxxx_/va_xxx_parameters b_relCAP_R3.0-1_INT5_xxxxx_va_xxx_parameters_p1
20120726 13:15:34 - [XXX] ERROR: Line rejected: copy xxxxxxxx_/xxxxxxx_view.tcl b_relCAP_R3.0-1_INT5_xxxxxx_view.tcl_p0
20120726 13:15:35 - [XXX] INFO: Line accepted: copy xxxxx_/xxxxxarchivetool.jar b_relEARLY_DROP1_xxxxxarchivetool.jar_xx
20120726 13:15:35 - [XXX] INFO: File extracted: b_relEARLY_DROP1_xxxxxarchivetool.jar_xx
Hint
I did some of the testing that #BaL proposed and found out that the pattern matching works without the selection parenthesis.
if ($_[0] =~ m/^copy\s+.+?\s+.+?\_.+$/) {

Answer 1

The test : if ($file !~ "0") { is true when $file doesn't contain a 0 at any position which is the case of the last string only.
I guess you want to use : if ($file ne '0') { or even shorter : if ($file) {
Apart of this you should really use strict; and use warnings always.

Answer 2

What are you trying to match ? The last part ?
Don't use * if you know that you have something to match, use + instead :
if ($_[0] =~ m/^copy\s+.+?\s+(.\+?)$/) {
return $1;
}

Answer 3

I'm guessing that the last line of your test file is the only one that doesn't end with a "\n". Funny little buggers are always getting in the way.....

Answer 4

Change the comparison operator in your if statement from !~ to ne as you are making a string comparison. When I make this change, all log lines were accepted.
I tested this on perl 5.14.2, not 5.10, but I didn't use any special features. Give it a go! code is below:
use 5.14.2;
sub log_msg{
say shift;
}
sub parse_bl_line {
if ($_[0] =~ m/^copy\s+.*?\s+(.*?\_.*)/) {
return $1;
}
else {
log_msg("Line discarded: $_[0]", 4);
return "0";
}
}
my #bl_lines = (
"copy xxxxxx_/cpu b_relCAP_R3.0-1_INT5_xxxxx_cpu_p1",
"copy xxxxxxxx_/va_xxx_parameters b_relCAP_R3.0-1_INT5_xxxxx_va_xxx_parameters_p1",
"copy xxxxxxxx_/xxxxxxx_view.tcl b_relCAP_R3.0-1_INT5_xxxxxx_view.tcl_p0",
"copy xxxxx_/xxxxxarchivetool.jar b_relEARLY_DROP1_xxxxxarchivetool.jar_xx"
);
foreach(#bl_lines) {
my $file = parse_bl_line($_);
if ($file ne "0") { # Changed the comparison operator here
log_msg("Line accepted: $_", 4);
log_msg("File extracted: $file", 4);
}
else {
log_msg("Line rejected: $_", 2);
}
}