Improve example 18 for @omitDefault

[gkellogg]

The example works, but does not really show why you would ever use both @default and @omitDefault.

[iherman]

This issue was discussed in a meeting.

• ACTION: provide example in issue frame/41 of @omitdefault need (Dave Longley)
  View the transcript

  Remove @omitdefault
  Rob Sanderson: link: https://github.com/w3c/json-ld-framing/issues/41
  Gregg Kellogg: also: https://github.com/w3c/json-ld-framing/issues/46
  Rob Sanderson: The first issue we discussed briefly last call before we realized we needed to talk a bit more about it.
  Gregg Kellogg: Another issue is to provide a better example for its use.
  … Of @omitDefault.
  … The issue is suggesting that @omitDefault is not particularly useful when you can just omit when using default. I think Dave had alluded to some examples where it was useful and that’s why there’s an issue open to highlight where it’s actually useful.
  … Otherwise we could remove it from the spec.
  … The only way to make a default is to use @default.
  Dave Longley: There’s a few ways to have a default. There’s an interaction with explicit. A default of null, if the property is specified but not present. Then output has a default value of null
  … sometimes you don’t want it with a value of null, but instead absent.
  … Also, if you had specified a default, and some other properties to have flags on them.
  … a case would be when you say ‘foo’ and you want to embed:always for foo.
  … [example]
  Gregg Kellogg: Ok, I think you’ve made a case for why it needs to be there. Having implemented it I still don’t understand the need for it. As long as you take on the responsibility of better documenting the use of @omitDefault.
  … If you can provide an example so we can adequately spec it that would be sufficient.
  Action #1: provide example in issue frame/41 of @omitdefault need (Dave Longley)
  

[azaroth42]

Example in #41 seems very clear to me!

[dlongley]

@gkellogg,

The example works, but does not really show why you would ever use both @default and @omitDefault.

The issue isn't with specifying those two flags together, but rather that there is a "default @default" of null that you may want to selectively disable. This is particularly true when you need to specify other flags (like @embed as in the example). I agree that it would be silly to use both @omitDefault and @default on the same subsection of a frame.