Regex.bits.step: def of bend-kit-regex@0.8.0.0
Import: import bend-kit-regex@0.8.0.0/regex.bend as Regex
Lines 1231-1237 of bend-kit-regex@0.8.0.0/regex.bend: https://jend.leeeet.dev/read.txt?path=bend-kit-regex@0.8.0.0/regex.bend&start_line=1231&end_line=1237

import Base

# ponytail: one test per set in the program, not a table lookup; use per-byte tables if sets grow many.
def bits.step(xs: List<&2, Bit>, +cur: U32, +c: U32, acc: Bs) -> Bs:
  match xs:
    case Nil{}:
      acc
    case Con{Bit{+mask, neg, items, follow, fin, end}, t}:
      bits.step(t, cur, c, bits.char(U32.is_ne((cur .&. mask : U32), 0), c, neg, items, follow, fin, end, acc))

Uses (7):
  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=Base/base.bend&name=U32.and
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.is_ne
  https://jend.leeeet.dev/definition.txt?path=bend-kit-regex@0.8.0.0/regex.bend&name=Bit
  https://jend.leeeet.dev/definition.txt?path=bend-kit-regex@0.8.0.0/regex.bend&name=Bs
  https://jend.leeeet.dev/definition.txt?path=bend-kit-regex@0.8.0.0/regex.bend&name=bits.char