You can use Getopt::Long for much of this:

#!/usr/bin/perl -w
use strict;
use Getopt::Long;
use Data::Dumper;

my @options = (-something => 'abc', -xyz => -abc => 'def', 'leftover')
+;
my @leftovers;
my %opts;

my @save_ARGV = @ARGV;

{
 local @ARGV = @options;

 my $result = GetOptions(\%opts, 'something=s','xyz','abc=s');
 @leftovers = @ARGV;
}

print Dumper(\%opts);
print Dumper(\@leftovers);
print Dumper(\@ARGV);
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