yaml_adv

# An example from https://en.wikipedia.org/wiki/YAML#Advanced_components
# pretty printed as .json after "expansion":
$> cat /tmp/sample.yaml                                                                     
# sequencer protocols for Laser eye surgery
---
- step:  &id001                  # defines anchor label &id001
    instrument:      Lasik 2000
    pulseEnergy:     5.4
    pulseDuration:   12
    repetition:      1000
    spotSize:        1mm

- step: &id002
    instrument:      Lasik 2000
    pulseEnergy:     5.0
    pulseDuration:   10
    repetition:      500
    spotSize:        2mm
- step: *id001                   # refers to the first step (with anchor &id001)
- step: *id002                   # refers to the second step
- step:
    <<: *id001
    spotSize: 2mm                # redefines just this key, refers rest from &id001
- step: *id002


$> python -c 'import yaml, json; print(json.dumps(yaml.load(open("/tmp/sample.yaml")), indent=2))'
[
  {
    "step": {
      "pulseEnergy": 5.4, 
      "instrument": "Lasik 2000", 
      "repetition": 1000, 
      "spotSize": "1mm", 
      "pulseDuration": 12
    }
  }, 
  {
    "step": {
      "pulseEnergy": 5.0, 
      "instrument": "Lasik 2000", 
      "repetition": 500, 
      "spotSize": "2mm", 
      "pulseDuration": 10
    }
  }, 
  {
    "step": {
      "pulseEnergy": 5.4, 
      "instrument": "Lasik 2000", 
      "repetition": 1000, 
      "spotSize": "1mm", 
      "pulseDuration": 12
    }
  }, 
  {
    "step": {
      "pulseEnergy": 5.0, 
      "instrument": "Lasik 2000", 
      "repetition": 500, 
      "spotSize": "2mm", 
      "pulseDuration": 10
    }
  }, 
  {
    "step": {
      "pulseEnergy": 5.4, 
      "instrument": "Lasik 2000", 
      "repetition": 1000, 
      "spotSize": "2mm", 
      "pulseDuration": 12
    }
  }, 
  {
    "step": {
      "pulseEnergy": 5.0, 
      "instrument": "Lasik 2000", 
      "repetition": 500, 
      "spotSize": "2mm", 
      "pulseDuration": 10
    }
  }
]