Schema for Skeleton Empty non-null object/array/string

---
$id: https://skeleton.botmd.io/skeleton/Empty.schema
$schema: http://json-schema.org/draft-07/schema#

title: Empty non-null object/array/string
description: Convenience schema for validating non-null empty data.

oneOf:
  - title: Empty array
    type: array
    maxItems: 0
  - title: Empty object
    type: object
    additionalProperties: false
  - title: Empty string
    type: string
    const: ""
#end oneOf