ConstructionContractPROOF.attached_length: def of bendtorch-core@0.1.0.0
Import: import bendtorch-core@0.1.0.0/src/tensor/construction_contract_PROOF.bend as ConstructionContractPROOF
Lines 237-264 of bendtorch-core@0.1.0.0/src/tensor/construction_contract_PROOF.bend: https://jend.leeeet.dev/read.txt?path=bendtorch-core@0.1.0.0/src/tensor/construction_contract_PROOF.bend&start_line=237&end_line=264

import Base
import bendtorch-core@0.1.0.0/src/shape/core.bend as Shape
import bendtorch-core@0.1.0.0/src/shape/nat_proofs.bend as Nats
import bendtorch-core@0.1.0.0/src/storage/main.bend as Storage
import bendtorch-core@0.1.0.0/src/tensor/core.bend as Core
import bendtorch-core@0.1.0.0/src/tensor/lifecycle.bend as Lifecycle
import bendtorch-core@0.1.0.0/src/tensor/allocation_PROOF.bend as AllocationProof
import bendtorch-core@0.1.0.0/src/tensor/observation.bend as Observation

def attached_length(+shape: Shape.Shape, +index: U32, +length: Nat,
  decision: Shape.BoolCase<Nat.is_eq(length, Shape.elements(shape))>, storage: Storage.Storage,
  -exact: {Lifecycle.logical_length(storage) == length : Nat}, counted: {length == Shape.elements(shape) : Nat},
  kept: {Lifecycle.retained_read(Storage.get(storage, index)) == Shape.logical_numel(Shape.dimensions(shape)) : Nat}) ->
  {Observation.after_length(shape, index, Core.attach_decided(shape, storage, length, exact, decision)) ==
    Some{Shape.logical_numel(Shape.dimensions(shape))} : Maybe<&2, Nat>}:
  match decision:
    case Shape.BFalse{no}:
      Empty.absurd({None{} == Some{Shape.logical_numel(Shape.dimensions(shape))} : Maybe<&2, Nat>},
        Nats.contradiction(Nat.is_eq(length, Shape.elements(shape)), AllocationProof.natural_equal_true(length, Shape.elements(shape), counted), no))
    case Shape.BTrue{yes}:
      Equal.cong(Nat, Maybe<&2, Nat>, number => Some{number},
        Observation.after_length_pair(shape, Core.read_flat(shape,
          Core.TTensor{storage, Equal.trans(Nat, Lifecycle.logical_length(storage), length, Shape.logical_numel(Shape.dimensions(shape)), exact,
            Equal.trans(Nat, length, Shape.elements(shape), Shape.logical_numel(Shape.dimensions(shape)),
              Lifecycle.natural_equal(length, Shape.elements(shape), yes), Shape.elements_exact(shape)))}, index)),
        Shape.logical_numel(Shape.dimensions(shape)),
        Equal.trans(Nat,
          Observation.after_length_pair(shape, Core.read_flat(shape,
            Core.TTensor{storage, Equal.trans(Nat, Lifecycle.logical_length(storage), length, Shape.logical_numel(Shape.dimensions(shape)), exact,
              Equal.trans(Nat, length, Shape.elements(shape), Shape.logical_numel(Shape.dimensions(shape)),
                Lifecycle.natural_equal(length, Shape.elements(shape), yes), Shape.elements_exact(shape)))}, index)),
          Lifecycle.retained_read(Storage.get(storage, index)), Shape.logical_numel(Shape.dimensions(shape)),
          length_projection(shape, storage,
            Equal.trans(Nat, Lifecycle.logical_length(storage), length, Shape.logical_numel(Shape.dimensions(shape)), exact,
              Equal.trans(Nat, length, Shape.elements(shape), Shape.logical_numel(Shape.dimensions(shape)),
                Lifecycle.natural_equal(length, Shape.elements(shape), yes), Shape.elements_exact(shape))),
            index, Storage.get(storage, index), {==}), kept))

Uses (26):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Empty.absurd
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.cong
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.trans
  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=U32
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/shape/core.bend&name=BoolCase
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/shape/core.bend&name=Shape
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/shape/core.bend&name=dimensions
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/shape/core.bend&name=elements
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/shape/core.bend&name=elements_exact
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/shape/core.bend&name=logical_numel
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/shape/nat_proofs.bend&name=contradiction
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/storage/main.bend&name=Storage
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/storage/main.bend&name=get
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/allocation_PROOF.bend&name=natural_equal_true
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/construction_contract_PROOF.bend&name=length_projection
  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=attach_decided
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/core.bend&name=read_flat
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/lifecycle.bend&name=logical_length
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/lifecycle.bend&name=natural_equal
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/lifecycle.bend&name=retained_read
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/observation.bend&name=after_length
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/tensor/observation.bend&name=after_length_pair