[sophiabits]

Type-prefixed IDs are the way to go. For completeness it's worth noting that the first example using the `string | 'currentNode'` type can be slightly improved in cases where you _do_ want autocomplete for known-good values but are still OK with accepting arbitrary string values:

  type Target = 'currentNode' | (string & {});
  const targets: Target[] = [
    'currentNode', // you get autocomplete hints for this!
    'somethingElse', // no autocomplete here, but it typechecks
  ];

[Waterluvian]

Is (string & {}) semantically intuitive or is it kind of a hack? I don’t understand what it’s supposed to mean.

[skybrian]

It's a useful hack. In JavaScript, there is no value that's both a string and an object. At runtime, it will just be a string. You can use it like a string and it will type-check, because it's a string plus some extra compile-time baggage, sort of like you subclassed the string type. ('&' is a subtype operation.)

When converting something to this type, it will fail unless you cast it, but it's a compile-time cast. At runtime, there's no conversion.

This is essentially "lying" to the type checker in order to extend it.