#!/usr/bin/perl

use Getopt::Declare;

my $args = new Getopt::Declare <<'EOPARAM';

    [strict]
    -e <env>            Collect data for systems in one env (can be used with -t)
                    
    -t <type>           Collect data for one type of system (can be used with -e)
                    
    -s <systemname>     Collect data for one system  [excludes: -e -t]
    
    --
    
EOPARAM

for ( qw(-e -s -t) )
{
    print  "Using value: ", $args->{$_}." for switch $_\n"
            if $args->{$_};
}
__END__
perl 559575.pl -s quux -e foo -t bar

##</code><code>##

Error: parameter '-e' not allowed with parameter '-s'
Error: parameter '-t' not allowed with parameter '-s'
Error: unrecognizable argument ('foo')
Error: unrecognizable argument ('bar')

(try '559575.pl -help' for more information)