Zlib.zl.head: def of bend-kit-zlib@0.5.1.0
Import: import bend-kit-zlib@0.5.1.0/zlib.bend as Zlib
Lines 739-745 of bend-kit-zlib@0.5.1.0/zlib.bend: https://jend.leeeet.dev/read.txt?path=bend-kit-zlib@0.5.1.0/zlib.bend&start_line=739&end_line=745

import Base
import bend-kit-bytes@0.3.3.0/bytes.bend as Bytes

def zl.head(r: Bytes.Bytes & Maybe<&2, U32>) -> Maybe<&1, Bytes.Bytes>:
  (b, m) = r
  match m:
    case None{}:
      None{}
    case Some{+h}:
      zl.go(zl.ok(U32.shrn(h, 8n), U32.and(h, 255)), b)

Uses (9):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Maybe
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Pair
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Sigma
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.and
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.shrn
  https://jend.leeeet.dev/definition.txt?path=bend-kit-bytes@0.3.3.0/bytes.bend&name=Bytes
  https://jend.leeeet.dev/definition.txt?path=bend-kit-zlib@0.5.1.0/zlib.bend&name=zl.go
  https://jend.leeeet.dev/definition.txt?path=bend-kit-zlib@0.5.1.0/zlib.bend&name=zl.ok