Lrw.CrLrw.key: def of bend-osdev-crypto@0.1.0.0
Import: import bend-osdev-crypto@0.1.0.0/lrw.bend as Lrw
Lines 115-123 of bend-osdev-crypto@0.1.0.0/lrw.bend: https://jend.leeeet.dev/read.txt?path=bend-osdev-crypto@0.1.0.0/lrw.bend&start_line=115&end_line=123

import Base
import bend-osdev-bytes@0.1.0.0/bytes.bend as B
import bend-osdev-gf@0.1.0.0/gf128.bend as G
import bend-osdev-crypto@0.1.0.0/crypto.bend as Cr

# a raw key: the cipher's key followed by the 16-byte tweak key
# (CrBadKeyLength for a key of 16 bytes or fewer, or one the cipher refuses)
def CrLrw.key(~K: Data, ~key: B.Octets -> Result<&2, &2, Cr.CrError, K>, +o: B.Octets) -> Result<&2, &2, Cr.CrError, CrLrwKey<K>>:
  +n = B.Octets.len(o)
  do Result<&2, &2, Cr.CrError, CrLrwKey<K>>:
    Cr.CrError.check(Nat.is_lt(16n, n), Cr.CrBadKeyLength{n})
    k : K <- key(B.Octets.take(Nat.sub(n, 16n), o))
    t : G.Gf128 <- cr.lrw.gf(n, G.Gf128.of_octets(B.Octets.drop(Nat.sub(n, 16n), o)))
    return CrLrwKey{k, t}

Uses (16):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.is_lt
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.sub
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Result
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Result.bind
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Result.pure
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Unit
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-bytes@0.1.1.0/bytes.bend&name=Octets
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-bytes@0.1.1.0/bytes.bend&name=Octets.drop
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-bytes@0.1.1.0/bytes.bend&name=Octets.len
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-bytes@0.1.1.0/bytes.bend&name=Octets.take
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-crypto@0.1.0.0/crypto.bend&name=CrError
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-crypto@0.1.0.0/crypto.bend&name=CrError.check
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-crypto@0.1.0.0/lrw.bend&name=CrLrwKey
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-crypto@0.1.0.0/lrw.bend&name=cr.lrw.gf
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-gf@0.1.1.0/gf128.bend&name=Gf128
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-gf@0.1.1.0/gf128.bend&name=Gf128.of_octets