[Compiler.saveMono] size: 1
    def foo._lam_0 x x.1 : Nat :=
      let _x.2 := Nat.add x.1 x;
      return _x.2
[Compiler.saveMono] size: 2
    def foo x xs : List Nat :=
      let _f.1 := foo._lam_0 x;
      let _x.2 := map _f.1 xs;
      return _x.2
[Compiler.saveMono] size: 2
    def boo x xs : List Nat :=
      let _f.1 := foo._lam_0 x;
      let _x.2 := map _f.1 xs;
      return _x.2