Cbor.step.head: def of bend-kit-cbor@0.3.0.0
Import: import bend-kit-cbor@0.3.0.0/cbor.bend as Cbor
Lines 675-681 of bend-kit-cbor@0.3.0.0/cbor.bend: https://jend.leeeet.dev/read.txt?path=bend-kit-cbor@0.3.0.0/cbor.bend&start_line=675&end_line=681

import Base

def step.head(stack: List<&1, Frame>, +len: U32, r: Array<U32> & Maybe<&2, Hd>) -> Array<U32> & St:
  (a, h) = r
  match h:
    case Some{Hd{+major, +ai, +arg, +i}}:
      item.hd(U32.is_eq(ai, 31), major, ai, arg, i, a, len, stack)
    case None{}:
      (a, SFail{})

Uses (11):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Array
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  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.is_eq
  https://jend.leeeet.dev/definition.txt?path=bend-kit-cbor@0.3.0.0/cbor.bend&name=Frame
  https://jend.leeeet.dev/definition.txt?path=bend-kit-cbor@0.3.0.0/cbor.bend&name=Hd
  https://jend.leeeet.dev/definition.txt?path=bend-kit-cbor@0.3.0.0/cbor.bend&name=St
  https://jend.leeeet.dev/definition.txt?path=bend-kit-cbor@0.3.0.0/cbor.bend&name=item.hd