Hologram v0.8.0: Elixir Gets JavaScript Interop

Massive release!

I’ve not played with the new JS interop, but the API looks very well considered. Hologram is moving into very interesting territory.

I look forward to continuing to contribute and to using the project for something real sometime soon.

Thank you @mward-sudo! It was a massive amount of work indeed - I think @robak86 aged about 5 years during the API design sessions alone. The fact that he still answers my phone calls is either a testament to his patience or evidence that he hasn’t figured out how to block a number yet… Or maybe he just picks up out of morbid curiosity about what I’ll ask next.

Amazing! Looks very comprehensive.

I’m sure y’all considered this as part of the design but I can’t help but think how clean it’d be to drop the brackets and create the list as an implementation detail under the hood.

So this

result =
  :Decimal
  |> JS.new([100])
  |> JS.call(:plus, [23])
  |> JS.call(:toNumber, [])  

becomes

result =
  :Decimal
  |> JS.new(100)
  |> JS.call(:plus, 23)
  |> JS.call(:toNumber)  

Unfortunately there are two problems with dropping the brackets:

1. List ambiguity - JS.call(:obj, :processList, [1, 2, 3]) becomes impossible to distinguish between one argument (the array [1, 2, 3]) and three separate arguments.

2. Arity clash - JS.call/2 calls a standalone function, JS.call/3 calls a method on a receiver. If args were optional, JS.call(:Decimal, :toNumber) could be either call/2 with one arg or call/3 with no args.

The explicit args list is also consistent with Kernel.apply/3, which always requires the args list. I actually considered naming it JS.apply at one point, so the parallel is intentional.