Hi all.

I just noticed something I can't understand with Getopt::Long yesterday. From the manual:

Options with multiple values
Options sometimes take several values. For example, a program could use multiple directories to search for library files:
    --library lib/stdlib --library lib/extlib
To accomplish this behaviour, simply specify an array reference as the destination for the option:
    GetOptions ("library=s" => \@libfiles);
Alternatively, you can specify that the option can have multiple values by adding a "@", and pass a scalar reference as the destination:
    GetOptions ("library=s@" => \$libfiles);

And this is what I have

use strict;
use warnings;
use Getopt::Long;
use Data::Dumper;
##### THREE VARIATIONS #####
## Does work:
my $options_ok = GetOptions ('option=s@' => \(our $option_array_ref));
my @option_array = @$option_array_ref;
## Does work:
our $option_array;
my $options_ok = GetOptions ('option=s' => \@option_array);
## Doesn't work:
my $options_ok = GetOptions ('option=s' => \(our @option_array));

##### COMMON CODE #####
if (not $options_ok) {
    print "Problem with options\n";
    exit -1;
}
print Dumper(@option_array);
exit 0;

[download]

Run with something like:

perl script.pl --option OPTION1 --option OPTION2

[download]
The strange thing is that this works for a single argument option: 
my $options_ok = GetOptions ('option=s' => \(our $option_variable));

[download]

So I had a bunch of those (saves lines for declaration of the variables), and when I wanted to switch one into a multi-value version, it didn't behave as I expected…

Wonder if anybody has an explanation, it must have to do with how references to variables and strings are returned on declaration, but it's not clear in my mind.
Any insights appreciated.

Cheers, Mark Collins.

In reply to Issue with multiple options for a Getopt::Long argument by Anonymous Monk

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