Chacha.block_rounds: def of bend-collections@1.0.0.0
Import: import bend-collections@1.0.0.0/spec/crypto/chacha.bend as Chacha
Lines 117-123 of bend-collections@1.0.0.0/spec/crypto/chacha.bend: https://jend.leeeet.dev/read.txt?path=bend-collections@1.0.0.0/spec/crypto/chacha.bend&start_line=117&end_line=123

import Base

# The same, entered through a match on the key's first cell. Both arms are
# block_body; the match only keeps the proof checker from evaluating the
# rounds on a symbolic key (it compares types by evaluating them).
def block_rounds(+n: Nat, key: List<&2, U32>, counter: U32, +nonce: List<&2, U32>) -> List<&2, U32>:
  match key:
    case Nil{}: block_body(n, Nil{}, counter, nonce)
    case b <> rest: block_body(n, b <> rest, counter, nonce)

Uses (4):
  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=bend-collections@1.0.0.0/spec/crypto/chacha.bend&name=block_body