X25519.valid_bytes: def of bend-collections@1.0.0.0
Import: import bend-collections@1.0.0.0/src/crypto/curve25519/x25519.bend as X25519
Lines 128-142 of bend-collections@1.0.0.0/src/crypto/curve25519/x25519.bend: https://jend.leeeet.dev/read.txt?path=bend-collections@1.0.0.0/src/crypto/curve25519/x25519.bend&start_line=128&end_line=142

import Base

# 32 values, each below 256
def valid_bytes(n: Nat, xs: List<&2, U32>) -> Bool:
  match n:
    case 0n:
      match xs:
        case Nil{}:
          True{}
        case Con{x, xt}:
          False{}
    case 1n+m:
      match xs:
        case Nil{}:
          False{}
        case Con{x, xt}:
          Bool.and(U32.is_lt(x, 256), valid_bytes(m, xt))

Uses (6):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.and
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.is_lt