filling structure hole

Stream: general

[Kevin Buzzard]

With this Lean file:

import data.equiv.basic

variable (X : Type)

example : set X ≃ X → Prop := {! !}

if I select "generate a skeleton..." I get the attached pop-up in VS Code (too many constructors state: X : Type ⊢ set X ≃ X → Prop) too_many_constructors.png

[Kevin Buzzard]

oh got it (X \to Prop)