DynamicArray.tl_go_at: def of bend-collections@1.0.0.0
Import: import bend-collections@1.0.0.0/src/containers/dynamic_array.bend as DynamicArray
Lines 440-447 of bend-collections@1.0.0.0/src/containers/dynamic_array.bend: https://jend.leeeet.dev/read.txt?path=bend-collections@1.0.0.0/src/containers/dynamic_array.bend&start_line=440&end_line=447

import Base

# The executable to_list is the same indexed walk, compiled at a closed
# element type; proofs/dynamic_array/closed.bend proves the two agree.
def tl_go_at(~T: Data, k: Nat, acc: List<&2, T>, r: Array<Maybe<&2, T>> & Maybe<&2, T>) -> Array<Maybe<&2, T>> & List<&2, T>:
  match k r:
    case 0n Tuple{a, x}:
      (a, acc)
    case 1n+ +m Tuple{a, x}:
      tl_go_at(~T, m, cons_some(T, x, acc), Array.get(Maybe<&2, T>, a, U32.from_nat(dec1(m))))

Uses (10):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Array
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Array.get
  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=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=U32.from_nat
  https://jend.leeeet.dev/definition.txt?path=bend-collections@1.0.0.0/src/containers/dynamic_array.bend&name=cons_some
  https://jend.leeeet.dev/definition.txt?path=bend-collections@1.0.0.0/src/containers/dynamic_array.bend&name=dec1