YGNI - YAML's Gonna Need It

A YAML Schema Language Proposal by Ingy

An Example Schema

This is just some stream of conciousness stuff. Not done yet...

  path: //
  tag:  '!<,2004:person>
  kind: map
    - key: name
      value: '!!str'
      required: y
    - key: age
      value: '!!int'
      required: y
    - key: nationality
      value: '!nationality'

  type: enum
  values: [black, white, yellow, red, green]

Related Schema

json has nearly a  fully developed schema that has been in the works for about 5 years. Considering the similarities and overlap between the two formats, it might be fairly straightforward to adapt the json schema for yaml.