lean4-htt/tests/lean/run/hcongr.lean
Leonardo de Moura b92a2cd918 feat: heterogeneous congruence theorems
These theorems are needed to implement the congruence closure module.
2021-09-14 17:23:12 -07:00

24 lines
685 B
Text
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

import Lean
inductive Vec (α : Type u) : Nat → Type u
| nil : Vec α 0
| cons : α → Vec α n → Vec α (n+1)
def Vec.map (f : α → β) : Vec α n → Vec β n
| nil => nil
| cons a as => cons (f a) (map f as)
open Lean
open Lean.Meta
def tstHCongr (f : Expr) : MetaM Unit := do
let result ← mkHCongr f
check result.proof
IO.println (← ppExpr result.type)
IO.println (← ppExpr result.proof)
unless (← isDefEq result.type (← inferType result.proof)) do
throwError "invalid proof"
#eval tstHCongr (mkConst ``Vec.map [levelZero, levelZero])
#eval tstHCongr (mkApp2 (mkConst ``Vec.map [levelZero, levelZero]) (mkConst ``Nat) (mkConst ``Nat))