From: "baweaver (Brandon Weaver)" <noreply@...>
Date: 2022-03-04T08:45:37+00:00
Subject: [ruby-core:107774] [Ruby master Misc#18609] keyword decomposition in enumerable (question/guidance)

Issue #18609 has been updated by baweaver (Brandon Weaver).


sawa (Tsuyoshi Sawada) wrote in #note-2:
> Perhaps, you can also do this:
> 
> ```ruby
> drafts.each do |draft|
>   name, mod, image = draft.values_at(:name, :mod, :image)
>   ...
> ```
> 
> or if you are sure about the order of the keys, even this (although fragile):
> 
> ```ruby
> drafts.each do |draft|
>   name, mod, image = draft.values
>   ...
> ```

If we want to be _really_ interesting we can take a note from pattern matching on those:

```ruby
drafts.each do |name:, mod: { id:, creator: }, image: { url: }|
  # ...
end
```

But that's pretty overkill and Whitequark / parser creators would hate us for it.

Anyways, if it's a regression from 3.1.0 to 3.1.1 should probably be patched back, as that's been something I've used myself in the past too.

----------------------------------------
Misc #18609: keyword decomposition in enumerable (question/guidance)
https://bugs.ruby-lang.org/issues/18609#change-96695

* Author: Ethan (Ethan -)
* Status: Open
* Priority: Normal
----------------------------------------
There is a pattern that I have used somewhat often in ruby 2, decomposing hash keys as keyword arguments to blocks for Enumerable, which no longer works in ruby 3. I'm wondering if there is a better way that I am missing (I couldn't find any discussion of this particular thing searching this tracker).

```ruby
drafts = [
  {name: 'draft4', mod: :Draft04, image: 'draft4.png'},
  {name: 'draft6', mod: :Draft06, image: 'draft6.jpg'},
]

# ruby 2
drafts.each do |name: , mod: , image: |
  ...

# ruby 3
drafts.each do |draft|
  name = draft[:name]
  mod = draft[:mod]
  image = draft[:image]
  ...
```

the latter is much more cumbersome, but seems necessary with the switch in keyword argument handling in ruby 3.

I can refactor to `name, mod, image = draft[:name], draft[:mod], draft[:image]`. that is a little better but still more verbose and repetitive than it used to be, and with more keys the line gets very long.

I am expecting this pattern is just a casualty of the keyword split that I will have to rewrite and this issue can be closed, but hoping there may be some better option I have missed.




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