YAML anchors and variables - code reuse question

[inger_klekacz]

So, I'm familiar with the use of YAML anchors to create a "default" step, like so:

definitions:
  steps:
    - step: &baseline-step
        name: Build Front-End app on non-master branch
        script:
          - echo "hello world"


branches:
  master:
    - step:
        <<: *baseline-step
        name: Build Front-End app on Master branch

 But I'm not quite sure how to use variables in this context.

For example, I have 3 or 4 tasks that use exactly the same code, except that the object name is different, or a keyword arg value is different. I want to do something like this:

definitions:
  steps:
    - step: &baseline-step
        name: Build Front-End app on non-master branch
        script:
          - echo "hello world"
          - ./my_script.sh -i $MY_VAR


branches:
  master:
    - step:
        <<: *baseline-step
        name: Build Front-End app on Master branch
        MY_VAR: Prod          # would generate './my_script.sh -i Prod'
  dev:
    - step:
        <<: *baseline-step
        name: Build Front-End app on Dev branch
        MY_VAR: Dev           # would generate './my_script.sh -i Dev'

I feel like I'm misunderstanding variables. Like, there's a missing piece here. My goal is code reusability, but it seems like without enabling...Deployments, maybe?...I can't use variables.

Can someone explain to me how to achieve this? I'm not the first person to ask this question, and it seems that nobody else has gotten a clear answer on this, either:

- YAML-anchors-Overriding-Reusing-deployment-variables 

- Variables-per-step-yaml-anchors/ 

- Is-it-possible-using-YAML-anchors-to-define-variables-that-you 

[BHARATHKUREK]

@inger_klekacz  you can use if loop to change the variable value based on your condition, so based on the condition satisfied $MY_VAR will pick that value and perform the action.