conditions (YAML only)

This variable is used for dynamic changes according to current conditions.

- type: item_definition
  a:1
  b:2
  conditions:
  - if: "%this.a% == 1" # will be true
    then:
      type: item_definition
    else:
      type: another_item_definition
  - if: "%this.b% == 1" # will be false
    then:
      disabled: true

For groovy equívalent look here: Render callback