BEGIN {
    my $haveTk= eval { require Tk; 1 };
    if(  ! $haveTk  ) {
        my $perl= "//tye-desk/perl/bin/perl.exe";
        warn "Switching to Tye's copy of Perl since Tk isn't installed...\n";
        die "Can't access $perl: $! ($^E)\n"
            unless  -f $perl;
        system( 1, $perl, $0, @ARGV );
        exit( 0 );
    }
}