LeanMachineLearning

transformHomToKernel🔗

Opaque

Recursive transformation from morphism expression in SFinKer to kernel expression.

🔗opaque
transformHomToKernel (e : Lean.Expr) (proofs : List Lean.Expr) : Lean.MetaM (Lean.Expr × List Lean.Expr)
transformHomToKernel (e : Lean.Expr) (proofs : List Lean.Expr) : Lean.MetaM (Lean.Expr × List Lean.Expr)

Code

partial def transformHomToKernel (e : Expr) (proofs : List Expr) :
    MetaM (Expr × List Expr)
Proof
do
  match e.getAppFn with
  | Expr.const ``tensorHom _ =>
    let args := e.getAppArgs
    let κ := args[args.size - 2]!
    let η := args[args.size - 1]!
    let ST := args[args.size - 3]!
    let SZ := args[args.size - 4]!
    let SY := args[args.size - 5]!
    let SX := args[args.size - 6]!
    let (κ', proofs_κ) ← transformHomToKernel κ proofs
    let (η', proofs_η) ← transformHomToKernel η proofs_κ
    let (X, Y, _, _) ← getTypesFromKernel κ'
    let (Z, T, _, _) ← getTypesFromKernel η'
    let parallelComp_hom_proof ← mkAppMInst ``parallelComp_hom
        #[SX, SY, SZ, ST, ← idME X, ← idME Y, ← idME Z, ← idME T, κ', η'] 2
    return (← mkAppM ``Kernel.parallelComp #[κ', η'], parallelComp_hom_proof :: proofs_η)
  | Expr.const ``CategoryStruct.comp _ =>
    let args := e.getAppArgs
    let κ := args[args.size - 2]!
    let η := args[args.size - 1]!
    let SY := args[args.size - 3]!
    let SX := args[args.size - 4]!
    let SZ := args[args.size - 5]!
    let (κ', proofs_κ) ← transformHomToKernel κ proofs
    let (η', proofs_η) ← transformHomToKernel η proofs_κ
    let (X, Y, _, _) ← getTypesFromKernel η'
    let (Z, _, _, _) ← getTypesFromKernel κ'
    let comp_hom_proof ← mkAppMInst ``comp_hom
        #[SX, SY, SZ, ← idME X, ← idME Y, ← idME Z, η', κ'] 2
    return (← mkAppM ``Kernel.comp #[η', κ'], comp_hom_proof :: proofs_η)
  | Expr.const ``CategoryStruct.id [xLvl, _] =>
    let args := e.getAppArgs
    let SX := args[args.size - 1]!
    let X ← getTypeFromSFinKer SX
    let mX' ← synthInstance (mkApp (mkConst ``MeasurableSpace [xLvl]) X)
    let id ← mkAppOptM ``Kernel.id #[X, mX']
    let id_hom_proof ← mkAppM ``id_hom #[SX, ← idME X]
    return (id, id_hom_proof :: proofs)
  | Expr.const ``ComonObj.counit [xLvl, _] =>
    let args := e.getAppArgs
    let SX := args[args.size - 2]!
    let X ← getTypeFromSFinKer SX
    let discard_kernel_const := mkConst ``Kernel.discard [xLvl, xLvl]
    let discard_const := mkConst ``counit [xLvl, xLvl, xLvl]
    let discard_hom_proof ← mkAppM' discard_const #[SX, ← idME X]
    return (← mkAppOptM' discard_kernel_const #[X, none], discard_hom_proof :: proofs)
  | Expr.const ``ComonObj.comul [xLvl, _] =>
    let args := e.getAppArgs
    let SX := args[args.size - 2]!
    let X ← getTypeFromSFinKer SX
    let copy_kernel_const := mkConst ``Kernel.copy [xLvl]
    let copy_hom_proof ← mkAppM ``comul #[SX, ← idME X]
    return (← mkAppOptM' copy_kernel_const #[X, none], copy_hom_proof :: proofs)
  | Expr.const ``Kernel.hom _ =>
    let args := e.getAppArgs
    let κ := args[args.size - 2]!
    return (κ, proofs)
  | Expr.const ``MonoidalCategory.whiskerLeft [eLvl, _] =>
    let (κ, kernel_id, SX, SY, SZ, X, Y, Z) ← deconstructWhiskersHomArgs e eLvl true
    let (κ', proofs_κ) ← transformHomToKernel κ proofs
    let whisker_left_hom_proof ← mkAppMInst ``Kernel.whiskerLeft
      #[SX, SY, SZ, ← idME X, ← idME Y, ← idME Z, κ'] 1
    return (← mkAppM ``Kernel.parallelComp #[kernel_id, κ'], whisker_left_hom_proof :: proofs_κ)
  | Expr.const ``MonoidalCategory.whiskerRight [eLvl, _] =>
    let (κ, kernel_id, SX, SY, SZ, X, Y, Z) ← deconstructWhiskersHomArgs e eLvl false
    let (κ', proofs_κ) ← transformHomToKernel κ proofs
    let whisker_right_hom_proof ← mkAppMInst ``Kernel.whiskerRight
      #[SX, SY, SZ, ← idME X, ← idME Y, ← idME Z, κ'] 1
    return (← mkAppM ``Kernel.parallelComp #[κ', kernel_id], whisker_right_hom_proof :: proofs_κ)
  | Expr.const ``Iso.hom _ =>
    let args := e.getAppArgs
    let iso := args[args.size - 1]!
    match iso.getAppFn with
    | Expr.const ``BraidedCategory.braiding _ =>
      let (braiding_expr, swap_hom_proof) ← deconstructBraiding iso
      return (braiding_expr, swap_hom_proof :: proofs)
    | Expr.const ``leftUnitor [eLvl, _] =>
      let (left_unitor_expr, left_unitor_hom_proof) ← deconstructUnitors iso eLvl true true
      return (left_unitor_expr, left_unitor_hom_proof :: proofs)
    | Expr.const ``rightUnitor [eLvl, _] =>
      let (right_unitor_expr, right_unitor_hom_proof) ← deconstructUnitors iso eLvl false true
      return (right_unitor_expr, right_unitor_hom_proof :: proofs)
    | Expr.const ``MonoidalCategory.associator [eLvl, _] =>
      let (associator_expr, associator_hom_proof) ← deconstructAssociator iso eLvl true
      return (associator_expr, associator_hom_proof :: proofs)
    | _ => throwError "Unexpected isomorphism {iso}."
  | Expr.const ``Iso.inv _ =>
    let args := e.getAppArgs
    let iso := args[args.size - 1]!
    match iso.getAppFn with
    | Expr.const ``BraidedCategory.braiding _ =>
      let (braiding_expr, swap_hom_proof) ← deconstructBraiding iso
      return (braiding_expr, swap_hom_proof :: proofs)
    | Expr.const ``leftUnitor [eLvl, _] =>
      let (left_unitor_expr, left_unitor_inv_hom_proof) ← deconstructUnitors iso eLvl true false
      return (left_unitor_expr, left_unitor_inv_hom_proof :: proofs)
    | Expr.const ``rightUnitor [eLvl, _] =>
      let (right_unitor_expr, right_unitor_inv_hom_proof) ← deconstructUnitors iso eLvl false false
      return (right_unitor_expr, right_unitor_inv_hom_proof :: proofs)
    | Expr.const ``MonoidalCategory.associator [eLvl, _] =>
      let (associator_expr, associator_inv_hom_proof) ← deconstructAssociator iso eLvl false
      return (associator_expr, associator_inv_hom_proof :: proofs)
    | _ => throwError "Unexpected isomorphism {iso}."
  | _ => throwError "Expected a hom expression, got: {e}."

Actions: Source · Open Issue

Meaning last changed in v4.34.0-rc2-1-g439785b (2026-08-23).

Self-contained, with its dependencies inlined and proofs replaced by sorry: download the raw file · open it in the Lean web editor.

Dependency graph

Nothing to draw. Its statement rests on no other declaration in this project, and names nothing from a package left unaudited — so the graph is this declaration alone. That is the answer, not a missing picture.

Audit surface: 0 project declarations, 4 external constants

✓ Proved: no sorry anywhere in its closure

This is the tool's own reading of one build's recorded axioms, and it is not robust against an author who wants it to pass. Checking meant to be relied on should go through Comparator, which replays the proof through the kernel from an export against an explicit list of permitted axioms.