Bytes.find.go: def of bend-kit-bytes@0.3.3.0
Import: import bend-kit-bytes@0.3.3.0/bytes.bend as Bytes
Lines 429-442 of bend-kit-bytes@0.3.3.0/bytes.bend: https://jend.leeeet.dev/read.txt?path=bend-kit-bytes@0.3.3.0/bytes.bend&start_line=429&end_line=442

import Base

# ponytail: naive search; a mismatch costs one byte read per position, but a repetitive needle is O(len * needle). Add a SWAR scan or two-way search if find gets hot.
# f counts the positions left after i.
def find.go(f: Nat, r: Array<U32> & Bool, +needle: String, +i: U32, +up: Bool) -> Array<U32> & Maybe<&2, U32>:
  match f:
    case 0n:
      (a, hit) = r
      (a, Bool.pick(Maybe<&2, U32>, hit, Some{i}, None{}))
    case 1n+p:
      (a, hit) = r
      match hit:
        case True{}:
          (a, Some{i})
        case False{}:
          find.go(p, at(a, needle, step(up, i)), needle, step(up, i), up)

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=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.pick
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Maybe
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  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=String
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=bend-kit-bytes@0.3.3.0/bytes.bend&name=at
  https://jend.leeeet.dev/definition.txt?path=bend-kit-bytes@0.3.3.0/bytes.bend&name=step