Sha.length_field: def of bend-collections@1.0.0.0
Import: import bend-collections@1.0.0.0/spec/crypto/sha.bend as Sha
Lines 44-47 of bend-collections@1.0.0.0/spec/crypto/sha.bend: https://jend.leeeet.dev/read.txt?path=bend-collections@1.0.0.0/spec/crypto/sha.bend&start_line=44&end_line=47

import Base

# 8*n = 256*(n/32) + 8*(n mod 32); avoids overflowing runtime Nat.
def length_field(+n: Nat) -> List<&2, U32>:
  List.append(&2, U32, octets(7n, Nat.div(n, 32n)),
    [U32.shln(U32.from_nat(Nat.mod(n, 32n)), 3n)])

Uses (9):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List.append
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.div
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.mod
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.from_nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.shln
  https://jend.leeeet.dev/definition.txt?path=bend-collections@1.0.0.0/spec/crypto/sha.bend&name=octets