Something like: (code tested)

use strict;
use warnings;
my $var1 ="a.pl";
my %hash = (
    "command1" => "type $var1"
);

system ($hash{"command1"});
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Update:

I was thinking of adding this update, and at the same time, I saw the reply from emilford. I like this better:

use strict;
use warnings;
my %hash = (
    "command1" => "type %s"
);
my $var1 ="a.pl";
system(sprintf($hash{"command1"}, $var1));
[download]