def lookup_naturals

bendtorch-core@0.1.0.0 · src/tensor/axis_algebra.bend:259

import Base
import bendtorch-core@0.1.0.0/src/shape/core.bend as Shape
import bendtorch-core@0.1.0.0/src/tensor/axis_spec.bend as Axis

259def lookup_naturals(+items: List<&2, U32>, +index: Nat) ->
260  {natural_value(Axis.lookup(U32, items, index)) == Axis.lookup(Nat, Shape.naturals(items), index) : Maybe<&2, Nat>}:
261  match items index:
262    case Nil{} 0n:
263      {==}
264    case Nil{} 1n+p:
265      {==}
266    case head <> tail 0n:
267      {==}
268    case head <> +tail 1n+p:
269      lookup_naturals(tail, p)