Chacha20poly1305.xseal: def of bend-collections@1.0.0.0
Import: import bend-collections@1.0.0.0/spec/crypto/chacha20poly1305.bend as Chacha20poly1305
Lines 64-67 of bend-collections@1.0.0.0/spec/crypto/chacha20poly1305.bend: https://jend.leeeet.dev/read.txt?path=bend-collections@1.0.0.0/spec/crypto/chacha20poly1305.bend&start_line=64&end_line=67

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

# XChaCha20-Poly1305: ChaCha20-Poly1305 under the HChaCha20 subkey of the
# first 16 nonce bytes, with the nonce 0x00000000 || nonce[16..24].
def xseal(+key: List<&2, U32>, +nonce: List<&2, U32>, +aad: List<&2, U32>, +pt: List<&2, U32>) -> List<&2, U32>:
  seal(CH.xsubkey(key, nonce), CH.xnonce(nonce), aad, pt)

Uses (5):
  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/spec/crypto/chacha20poly1305.bend&name=seal
  https://jend.leeeet.dev/definition.txt?path=bend-collections@1.0.0.0/spec/crypto/chacha.bend&name=xnonce
  https://jend.leeeet.dev/definition.txt?path=bend-collections@1.0.0.0/spec/crypto/chacha.bend&name=xsubkey