Or: 
my @a;
my @b;
GetOptions (
  "a=s" => \@a,
  "b=s" => \@b
);
@a = split(/,/,join(',',@a));
@b = split(/,/,join(',',@b));

if ( scalar(@a) !=2 || scalar(@b) !=2 ){
  # shout at user here
}

[download]
The command line in that case would look like either of these (both will work) 
perl the_script -a 1 -a 2 -b 10 -b 30

[download]
or 
perl the_script -a 1,2 -b 10,30

[download]
I think the requirement to either specify the option name along with a value or use comma-separation makes the command a little clearer to read. Personal preference really.

In reply to Re: GetOpts::long Multiple Parameters per option by tospo
in thread GetOpts::long Multiple Parameters per option by PyrexKidd

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