Bah, that should be

#!/usr/bin/perl --
use strict;
use warnings;

use Config;

Main( @ARGV );
exit( 0 );

sub Main {
    my $sep = $Config{path_sep};
    my $pat = 'export PATH=%s$PATH';
    $pat = 'set PATH=%s%%PATH%%'  if $sep eq ';' ;

    printf "$pat\n", join $sep, (
        uniq(
            grep length,
            grep defined,
            map { $Config{$_} }
            qw'
            installsitebin
            installvendorbin
            installbin
            installsitescript
            installvendorscript
            installscript
            '
        ),
      ),
      '';
}
sub uniq (@) {
    my %seen = ();
    grep { not $seen{$_}++ } @_;
}
__END__
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