use File::Copy qw();

if (-f "Normalize.xs") {
    print STDERR "Disabling XS in sources...\n";

    die "***** Failed, sources could be inconsistent! *****\n"
     unless File::Copy::move('MANIFEST',	'MANIFEST.X')
	and File::Copy::move('MANIFEST.N',	'MANIFEST')
	and File::Copy::move('Normalize.pm',	'Normalize.pmX')
	and File::Copy::move('Normalize.xs',	'Normalize.xsX')
	and File::Copy::move('Normalize.pmN',	'Normalize.pm');
}