How to Include 'default' Key in YAML Output

[kaniza]

I'm using Pkl version 0.27.1 on macOS.

% pkl --version
Pkl 0.27.1 (macOS 15.1, native)

I want to write Pkl that produces YAML output like the following, but I'm having trouble figuring out how to do it.

list:
  default:
    value: dummy1
  mykey:
    value: dummy2

I understand that when I write Pkl as shown below, 'default' is omitted from the output by specification.

list {
    default {
        value = "dummy1"
    }
    mykey {
        value = "dummy2"
    }
}

$ pkl eval -f yaml sample.pkl

list:
  mykey:
    value: dummy2

So, I tried enclosing 'default' in backticks, but the result remained the same.

list {
    `default` {
        value = "dummy1"
    }
    mykey {
        value = "dummy2"
    }
}

$ pkl eval -f yaml sample.pkl

list:
  mykey:
    value: dummy2

How can I write the Pkl to produce YAML output that includes the 'default' key as shown above?

list:
  default:
    value: dummy1
  mykey:
    value: dummy2

[HT154]

You would need to either a) define a class with a property default or b) use Mapping with key "default". You're (implicitly) using Dynamic here, which has a property default that's marked hidden.

[kaniza]

@HT154 Thank you, I'll try.

[kaniza]

Here's the updated Pkl code that worked:

list = new Mapping {
    ["default"] {
        value = "dummy1"
    }
    ["mykey"] {
        value = "dummy2"	      
    }
}

Using this approach, the "default" key is no longer hidden, and the YAML output is as expected:

list:
  default:
    value: dummy1
  mykey:
    value: dummy2

Thanks for the guidance!