Vocabulary : Set₁
Vocabulary = String → Set

LV : Set
LV = String

record SimpleInterpretation (V : Vocabulary ) : Set where
 field
  IR : Set
  IS : V → IR
  IEXT : IR → IR × (IR ⊹ LV)

Error:
(String → Set) !=< Set of type Set₁
when checking that the expression V has type Set