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diff --git a/GetTypes.agda b/GetTypes.agda
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+module GetTypes where
+
+open import Level using () renaming (zero to ℓ₀)
+open import Data.Nat using (ℕ)
+open import Data.List using (List ; map)
+open import Data.Vec using (Vec) renaming (map to mapV)
+open import Function using (_∘_)
+open import Function.Equality using (_⟶_ ; _⟨$⟩_)
+open import Function.Injection using (module Injection) renaming (Injection to _↪_ ; id to id↪)
+open import Relation.Binary.PropositionalEquality using (_≗_) renaming (setoid to EqSetoid)
+open import Relation.Binary using (Setoid)
+open Injection using (to)
+
+open import Generic using (≡-to-Π)
+
+module ListList where
+  record Get : Set₁ where
+    field
+      get : {A : Set} → List A → List A
+      free-theorem : {α β : Set} → (f : α → β) → get ∘ map f ≗ map f ∘ get
+
+module VecVec where
+  record Get : Set₁ where
+    field
+      getlen : ℕ → ℕ
+      get : {A : Set} {n : ℕ} → Vec A n → Vec A (getlen n)
+      free-theorem : {α β : Set} (f : α → β) {n : ℕ} → get {_} {n} ∘ mapV f ≗ mapV f ∘ get
+
+module PartialVecVec where
+  record Get : Set₁ where
+    field
+      I : Setoid ℓ₀ ℓ₀
+      gl₁ : I ↪ EqSetoid ℕ
+      gl₂ : I ⟶ EqSetoid ℕ
+      get : {A : Set} {i : Setoid.Carrier I} → Vec A (to gl₁ ⟨$⟩ i) → Vec A (gl₂ ⟨$⟩ i)
+      free-theorem : {α β : Set} → (f : α → β) → {i : Setoid.Carrier I} → get {_} {i} ∘ mapV f ≗ mapV f ∘ get
+
+VecVec-to-PartialVecVec : VecVec.Get → PartialVecVec.Get
+VecVec-to-PartialVecVec G = record
+  { I = EqSetoid ℕ
+  ; gl₁ = id↪
+  ; gl₂ = ≡-to-Π getlen
+  ; get = get
+  ; free-theorem = free-theorem
+  } where open VecVec.Get G