%YAML 1.2
---
version: 1.1

var1:
  description: a first variable
  test:
    - '#b1b1b1'
    - '#b2b2b2'
  default: '#a1a1a1'
  regexp: ^#(?:[0-9a-f]{3}){1,2}$

var2:
  description: a second variable
  test:
    - '#b2b1b1'
    - '#b3b2b2'
  default:
    variable: _.var1
...