Chacha20poly1305.poly_key: def of bend-collections@1.0.0.0
Import: import bend-collections@1.0.0.0/src/crypto/aead/chacha20poly1305.bend as Chacha20poly1305
Lines 21-23 of bend-collections@1.0.0.0/src/crypto/aead/chacha20poly1305.bend: https://jend.leeeet.dev/read.txt?path=bend-collections@1.0.0.0/src/crypto/aead/chacha20poly1305.bend&start_line=21&end_line=23

import Base
import bend-collections@1.0.0.0/src/crypto/chacha/chacha20.bend as CH

# poly1305_key_gen: the first 32 bytes of the block with counter 0.
def poly_key(key: List<&2, U32>, nonce: List<&2, U32>) -> List<&2, U32>:
  CH.take(32n, CH.block_rounds(10n, key, 0, 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=U32
  https://jend.leeeet.dev/definition.txt?path=bend-collections@1.0.0.0/src/crypto/chacha/chacha20.bend&name=block_rounds
  https://jend.leeeet.dev/definition.txt?path=bend-collections@1.0.0.0/src/crypto/chacha/chacha20.bend&name=take