type:      seq                                # new rule
sequence:
  -
    type:      map                            # new rule
    mapping:
      name:
        type:       str                       # new rule
        required:   yes
      email:
        type:       str                       # new rule
        required:   yes
        pattern:    /@/
      password:
        type:       text                      # new rule
        length:     { max: 16, min: 8 }
      age:
        type:       int                       # new rule
        range:      { max: 30, min: 18 }
        # or assert: 18 <= val && val <= 30
      blood:
        type:       str                       # new rule
        enum:
          - A
          - B
          - O
          - AB
      birth:
        type:       date                      # new rule
      memo:
        type:       any                       # new rule