Comment by patrickdavey | Hacker News Reader

Comment by patrickdavey | Hacker News Reader

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Attributes do support defaults. You can absolutely do:

   attribute :my_time_at, :datetime, default: -> { Time.now }
   attribute :persisted, :boolean, default: false

What I like about the types is that it will automatically coerce the messy user data automatically (this is what AR is doing under the hood anyway right?), you can just be more intentional about it.

Anyway, glad you're happy with portrayal :) I definitely agree with you on the "freeze, read-onlyness" etc. being good things to have!

Ah, I accidentally lied by trying to reconstruct a vague memory, apologies. Now I'm remembering it in more detail.

It wasn't lack of defaults, it was handling of defaults. Portrayal does a couple of smart things like evaluating defaults in a specific order in the correct context (while still only evaluating once), such that this becomes possible:

    keyword :name
    keyword :greeting, default: proc { "Hello, #{name}" }

I like being able to do this. (This also works gracefully with subclassing.)

The coercion argument is good, but I'm not a fan of doing it implicitly. (This was the real counter-argument I should've made). I prefer to have a single place where input is entirely processed, such as a `from_params(params)`-style constructor. In that constructor you could either coerce, or do anything else with the input prior to passing it through to `.new`.

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