mits.copy_to(ns, mlen, mifrom, 0)
sits.copy_to(ns, slen, sifrom, mlen)
return new FlatString.full(ns, nlen, 0, length + s.length)
mits.copy_to(ns, mlen, mifrom, 0)
sits.copy_to(ns, slen, sifrom, mlen)
return new FlatString.full(ns, nlen, 0, length + s.length)