CorePROOF.prefix_extend: def of bendtorch-core@0.1.0.0
Import: import bendtorch-core@0.1.0.0/src/tensor/core_PROOF.bend as CorePROOF
Lines 799-816 of bendtorch-core@0.1.0.0/src/tensor/core_PROOF.bend: https://jend.leeeet.dev/read.txt?path=bendtorch-core@0.1.0.0/src/tensor/core_PROOF.bend&start_line=799&end_line=816

import Base
import bendtorch-core@0.1.0.0/src/shape/core.bend as Shape
import bendtorch-core@0.1.0.0/src/tensor/core.bend as Core
import bendtorch-core@0.1.0.0/src/tensor/elementwise.bend as Elementwise

def prefix_extend(+operation: Elementwise.Operation, +plan: Shape.BroadcastPlan,
  -original_left: Core.Dynamic, -original_right: Core.Dynamic, +cursor: Nat, +index: U32,
  -before: Core.Tensor<Shape.output_shape(plan)>, -after: Core.Tensor<Shape.output_shape(plan)>,
  -converted: {U32.to_nat(index) == cursor : Nat},
  -prefix: Elementwise.PrefixInvariant(operation, plan, original_left, original_right, cursor, Core.Packed{Shape.output_shape(plan), before}),
  -checked: Core.ObservationChecked(Core.Packed{Shape.output_shape(plan), after}, index),
  -observed: {Core.observe(Shape.output_shape(plan), after, index) == Elementwise.expected(operation, plan, original_left, original_right, index) : Maybe<&2, F32>},
  -frame: @+other: U32 -> @checked: Core.ObservationChecked(Core.Packed{Shape.output_shape(plan), before}, other) ->
    @different: {Nat.is_eq(U32.to_nat(index), U32.to_nat(other)) == False{} : Bool} ->
      Core.ObservationChecked(Core.Packed{Shape.output_shape(plan), after}, other) &
        {Core.observe(Shape.output_shape(plan), after, other) == Core.observe(Shape.output_shape(plan), before, other) : Maybe<&2, F32>}) ->
  PrefixModel<operation, plan, original_left, original_right, 1n+cursor, after>:
  PrefixModel{other => bound =>
    {\{Inl: earlier => prefix_previous(operation, plan, original_left, original_right, cursor, index, before, after, converted, prefix, frame, other, earlier);
      Inr: equal => prefix_equal(operation, plan, original_left, original_right, cursor, index, after, converted, checked, observed, other, equal)} :
      Either<Shape.LT(U32.to_nat(other), cursor), {U32.to_nat(other) == cursor : Nat}> ->
        (Core.ObservationChecked(Core.Packed{Shape.output_shape(plan), after}, other) &
          {Core.observe(Shape.output_shape(plan), after, other) == Elementwise.expected(operation, plan, original_left, original_right, other) : Maybe<&2, F32>})}(lt_previous_or_equal(U32.to_nat(other), cursor, bound))}

Uses (23):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Either
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=F32
  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=Nat.is_eq
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Pair
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.to_nat
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/shape/core.bend&name=BroadcastPlan
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/shape/core.bend&name=LT
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/shape/core.bend&name=output_shape
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/core.bend&name=Dynamic
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/core.bend&name=ObservationChecked
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/core.bend&name=Tensor
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/core.bend&name=observe
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/core_PROOF.bend&name=PrefixModel
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/core_PROOF.bend&name=lt_previous_or_equal
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/core_PROOF.bend&name=prefix_equal
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/core_PROOF.bend&name=prefix_previous
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/elementwise.bend&name=Operation
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/elementwise.bend&name=PrefixInvariant
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/elementwise.bend&name=expected