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use File::Copy qw();

if (-f "Collate.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('Collate.pm',	'Collate.pmX')
	and File::Copy::move('Collate.xs',	'Collate.xsX')
	and File::Copy::move('Collate.pmN',	'Collate.pm');
}