struct1.lean:9:14-9:17: error: Invalid resulting type: Expected a sort

Hint: Examples of valid sorts include `Type _`, `Sort _`, and `Prop`
struct1.lean:12:20-12:29: error: expected structure

Hint: This error is possibly due to a change in the `structure` syntax. Now the syntax is `structure S : Type extends P` rather than `structure S extends P : Type`.

The purpose of the change is to accommodate `structure S extends toP : P` syntax for naming parent projections.
struct1.lean:15:28-15:33: warning: Field `x` from `B` has already been declared
struct1.lean:16:1-16:2: error: Field `x` has already been declared in a parent structure
struct1.lean:17:30-17:35: warning: Duplicate parent structure `A`; skipping
struct1.lean:19:27-19:33: error: Field type mismatch: Field `x` from parent `B` has type
  Bool
but is expected to have type
  Nat
struct1.lean:30:1-30:2: error: Field `x` has already been declared
struct1.lean:33:1-33:2: error: Field `x` has already been declared in a parent structure
struct1.lean:36:6-36:10: error: Type mismatch
  true
has type
  Bool
but is expected to have type
  Nat
struct1.lean:39:1-39:2: error: Type mismatch
  true
has type
  Bool
but is expected to have type
  Nat
struct1.lean:42:12-42:16: error: Type mismatch
  true
has type
  Bool
but is expected to have type
  Nat
struct1.lean:45:0-45:13: error: Constructor cannot be marked `private` because it is already in a `private` structure

Hint: Remove `private` modifier from constructor
  p̵r̵i̵v̵a̵t̵e̵ ̵mk ::
struct1.lean:48:0-48:15: error: Constructor cannot be `protected` because this structure is `private`
struct1.lean:51:0-51:19: error: Field cannot be marked `protected` because this structure is `private`
Spriv : Type
struct1.lean:57:7-57:12: error(lean.unknownIdentifier): Unknown constant `S.mk2`