AxisAlgebra.product_01: def of bendtorch-core@0.1.0.0
Import: import bendtorch-core@0.1.0.0/src/tensor/axis_algebra.bend as AxisAlgebra
Lines 381-390 of bendtorch-core@0.1.0.0/src/tensor/axis_algebra.bend: https://jend.leeeet.dev/read.txt?path=bendtorch-core@0.1.0.0/src/tensor/axis_algebra.bend&start_line=381&end_line=390

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

def product_01(+dims: List<&2, Nat>, length: {List.length(&2, Nat, dims) == 2n : Nat}) -> {Shape.numel(Axis.order(Nat, dims, [0n, 1n])) == Shape.numel(dims) : Nat}:
  match dims:
    case Nil{}:
      Empty.absurd({Shape.numel(Axis.order(Nat, Nil{}, [0n, 1n])) == Shape.numel(Nil{}) : Nat}, nat_clash(0n, 2n, length, {==}))
    case +x0 <> Nil{}:
      Empty.absurd({Shape.numel(Axis.order(Nat, x0 <> Nil{}, [0n, 1n])) == Shape.numel(x0 <> Nil{}) : Nat}, nat_clash(1n, 2n, length, {==}))
    case +x0 <> +x1 <> Nil{}:
      {==}
    case +x0 <> +x1 <> +x2 <> +tail:
      Empty.absurd({Shape.numel(Axis.order(Nat, x0 <> x1 <> x2 <> tail, [0n, 1n])) == Shape.numel(x0 <> x1 <> x2 <> tail) : Nat}, nat_clash(3n+List.length(&2, Nat, tail), 2n, length, {==}))

Uses (7):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Empty.absurd
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List.length
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/shape/core.bend&name=numel
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/axis_algebra.bend&name=nat_clash
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/axis_spec.bend&name=order