documentation on default relationship models

[browner12]

in reference to laravel/framework#19733

[decadence]

What's about HasOne? Can you add note that withDefault is available for it? Or it is already somewhere in the docs?

[decadence]

Yep, there is no any mention about withDefault in docs.

[browner12]

@taylorotwell thoughts on this? I didn't want to duplicate documenting the withDefault method under every relation it is available in.

What if I made a top level heading at the very bottom (under 'Touching Parent Timestamps') that could be a more general description of it, and which relations it was available for? @sileence is working on it for some of the other relations right now, so then we could add them to the list when he's done.

[sileence]

It'd make sense to document the feature and mention the relations that support it. By the way here is the PR for morphOne laravel/framework#19788.

[taylorotwell]

I don't really mind duplicating a basic example of it under both sections. I can tolerate duplication more in docs than code because it's more of a user assistance thing.