Re: When would you use qr// on a literal string?

"it_says_BALLS_on_your forehead" <simon.chao@xxxxxxx> wrote in
news:1153145251.119197.122300@xxxxxxxxxxxxxxxxxxxxxxxxxxx:

I thought that qr was mainly used for pre-compiling variables into
regex patterns, but a colleague uses it like so:

my ( $name, $value ) = split qr/=/, $string;

Are there any benefits to doing this? He claims that the use of the
qr// op here can help capture an error if the STRING is not a valid
regex. Does this make any sense?

The first argument to split is a regex, whether you use regex notation or
not.

So, I am not fond of:

split '=', $string;

because it obscures that fact.

On the other hand, I don't see what additional mileage qr gets you other
than saying: I really want to signal that this is a regex to other
programmers.

As for what mileage that gets you in terms of preventing errors, take a
look at:

#!/usr/bin/perl

use strict;
use warnings;

my $data = 'name$sinan';

my @a = split '$', $data;
my @b = split /$/, $data;
my @c = split qr/$/, $data;

# correct
my @d = split /\$/, $data;

print "@a\n@b\n@c\n@d\n";

__END__

Sinan
.

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