Hacker News Reader

Hacker News

Comment by jrochkind1 | Hacker News Reader

Full thread

jrochkind1

Wait, what happens if you want keyword arguments?

View on HN

Their docs say that something like:

`def greet(name: String, greeting: String = "Hello"): String`

will work for kwargs with default values — https://type-ruby.github.io/docs/getting-started/understandi...

I think they've missed a trick there, they could have used `|` like low-type does.

e.g.

  def greet(name: String | "Hello"): String

I know it's all subjective but I think that reads better and it's valid ruby.

To be honest low-type with a static analysis tool would be my favourite syntax for this.

https://github.com/low-rb/low_type

That example is for positional args with default values, according to the example usage: `greet("Alice")`. Can't find ruby-style keyword args example, with or without default values. maybe no kw args in t-ruby?

Or wait, found examples that claims to be keyword arguments, but you define them just the same? I'm confused. https://type-ruby.github.io/docs/learn/functions/optional-re...

It would seem that in T-Ruby all arguments are keyword arguments, although they don’t really spell this out.

https://type-ruby.github.io/docs/learn/functions/optional-re...

Yeah, it doesn't work with keyword arguments. In the playground I tried a simple keyword with default value, and it converted to the wrong thing, as if "someone" was a valid type.

    def greet(name: "someone"): String
      "Hello, #{name}!"
    end

keyword arguments are, internally, syntactic sugar over a hash. It probably doesn't easily work with typing the explicit values of a raw hash

This hasn’t been true since Ruby 3.0. Keyword arguments are a core language feature with their own semantics.

Oh huh, TIL. Thanks for sharing!

The obvious thing that comes to mind when looking at their spotlight example.

However, no mention of this basic head scratcher in the docs. :rolling_eyes:

Reply on news.ycombinator.com