Zlib.gz.xlen: def of bend-kit-zlib@0.5.1.0
Import: import bend-kit-zlib@0.5.1.0/zlib.bend as Zlib
Lines 553-561 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=553&end_line=561

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

# RFC 1952 §2.3: after the fixed 10 bytes, optional FEXTRA, FNAME, FCOMMENT, FHCRC.
# Each step takes the buffer and the offset so far; None once a field runs past the end.
def gz.xlen(+off: U32, r: Bytes.Bytes & Maybe<&2, U32>) -> Bytes.Bytes & Maybe<&2, U32>:
  (b, m) = r
  match m:
    case None{}:
      (b, None{})
    case Some{+x}:
      (b, Some{(off + 2 + x : U32)})

Uses (6):
  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.add
  https://jend.leeeet.dev/definition.txt?path=bend-kit-bytes@0.3.3.0/bytes.bend&name=Bytes