def shared_of

bend-collections-laws-crypto@1.0.0.0 · src/crypto/kex.bend:58

import Base
import bend-collections-laws-crypto@1.0.0.0/src/crypto/curve25519/field.bend as F

58def shared_of(m: Maybe<&2, List<&2, U32>>) -> Maybe<&2, List<&2, U32>>:
59  match m:
60    case None{}:
61      None{}
62    case Some{+ss}:
63      nonzero(ss, U32.is_eq(F.sum_all(ss, 0), 0))