Regex, spaces in pattern stored in variable.

I have a list of strings, some contain spaces. The strings are used as
patterns for a regex match, they don't seem to be working! I tried
substituting the space with '\s' but I got warnings, and still no match.

I'm sure there's a way to do this, but Google isn't providing any
answers (more likely I don't know how to formulate a useful search).

Anyway, here's what I have:

#!/usr/bin/perl

use warnings;
use strict;

my @list = (
"Fred Flintstone",
"Barney Rubble",
);

while (<DATA>) {
my $string = chomp $_;
foreach (@list) {
if ( $string =~ /($_)/ ) {
print "Matched ", $1, "\n";
}
}
}

__DATA__
A man called Fred Flintstone lives in a cave.
Fred's neighbour is called Barney Rubble.
Fred is married to Wilma Flintstone and Barney Rubble is married to Betty.

Justin.

--
Justin C, by the sea.

Justin C <justin.0911@purestblue.com> writes:

> #!/usr/bin/perl
>
> use warnings;
> use strict;
>
> my @list = (
> "Fred Flintstone",
> "Barney Rubble",
> );
>
> while (<DATA>) {
> my $string = chomp $_;

'perldoc -f chomp' says:

[...] It returns the total number of characters removed from all its
arguments. [...]

So $string would have the value 1. Using the perl debugger it would
have been very easy to check that you assumptions about the content of
$string and $_ was true at the conditional.


> foreach (@list) {
> if ( $string =~ /($_)/ ) {
> print "Matched ", $1, "\n";
> }
> }
> }
>
> __DATA__
> A man called Fred Flintstone lives in a cave.
> Fred's neighbour is called Barney Rubble.
> Fred is married to Wilma Flintstone and Barney Rubble is married to Betty.
>
> Justin.

On 2010-01-06, Peter Makholm <peter@makholm.net> wrote:
> Justin C <justin.0911@purestblue.com> writes:
>
>> #!/usr/bin/perl
>>
>> use warnings;
>> use strict;
>>
>> my @list = (
>> "Fred Flintstone",
>> "Barney Rubble",
>> );
>>
>> while (<DATA>) {
>> my $string = chomp $_;
>
> 'perldoc -f chomp' says:
>
> [...] It returns the total number of characters removed from all its
> arguments. [...]

Doh!

Thank you.

Justin.

--
Justin C, by the sea.

Quoth Justin C <justin.0911@purestblue.com>:
> I have a list of strings, some contain spaces. The strings are used as
> patterns for a regex match, they don't seem to be working! I tried
> substituting the space with '\s' but I got warnings, and still no match.
>
> I'm sure there's a way to do this, but Google isn't providing any
> answers (more likely I don't know how to formulate a useful search).
>
> Anyway, here's what I have:
>
> #!/usr/bin/perl
>
> use warnings;
> use strict;
>
> my @list = (
> "Fred Flintstone",
> "Barney Rubble",
> );
>
> while (<DATA>) {
> my $string = chomp $_;

chomp;

> foreach (@list) {

It's very confusing to have several nested loops all looping with $_.

for my $match (@list) {

> if ( $string =~ /($_)/ ) {

You normally want \Q\E when interpolating a plain string into a regex:

if (/(\Q$match\E)/) {

Ben

On 2010-01-06, Ben Morrow <ben@morrow.me.uk> wrote:
>
> Quoth Justin C <justin.0911@purestblue.com>:
>> I have a list of strings, some contain spaces. The strings are used as
>> patterns for a regex match, they don't seem to be working! I tried
>> substituting the space with '\s' but I got warnings, and still no match.
>>
>> I'm sure there's a way to do this, but Google isn't providing any
>> answers (more likely I don't know how to formulate a useful search).
>>
>> Anyway, here's what I have:
>>
>> #!/usr/bin/perl
>>
>> use warnings;
>> use strict;
>>
>> my @list = (
>> "Fred Flintstone",
>> "Barney Rubble",
>> );
>>
>> while (<DATA>) {
>> my $string = chomp $_;
>
> chomp;
>
>> foreach (@list) {
>
> It's very confusing to have several nested loops all looping with $_.
>
You're telling me!


> for my $match (@list) {
>
>> if ( $string =~ /($_)/ ) {
>
> You normally want \Q\E when interpolating a plain string into a regex:
>
> if (/(\Q$match\E)/) {

Ah, yes, I see. That makes sense (this is, I think, my first pattern in
a scalar).

>
> Ben
>


Justin.

--
Justin C, by the sea.