import Lean.Meta
open Lean
open Lean.Meta

universes u v w

abbrev M := ExceptT String $ MetaM

def testM {α} [HasBeq α] [HasToString α] (x : M α) (expected : α)  : MetaM Unit := do
r ← x;
match r with
| Except.ok a    => unless (a == expected) $ throwOther ("unexpected result " ++ toString a)
| Except.error e => throwOther ("FAILED: " ++ e)

@[noinline] def act1 : M Nat :=
throwThe Exception $ Exception.other Syntax.missing "Error at act1"

def g1 : M Nat :=
catchThe Meta.Exception
  (catch act1 (fun ex => pure 100))
  (fun ex => pure 200)

#eval testM g1 200

@[noinline] def act2 : M Nat :=
throw "hello world"

def g2 : M Nat :=
catchThe Meta.Exception
  (catch act2 (fun ex => pure 100))
  (fun ex => pure 200)

#eval testM g2 100