Issue #15723 has been updated by bozhidar (Bozhidar Batsov).


> While I'm not totally against your opinion, I would like you to understand that this feature was not made out of thin air; it was feature requested. People think this is a neat feature. If you are against the feature itself not against the syntax, please show us it harms more than it benefits.

Every language change obviously comes at a cost - it affects every tool that does some AST-based analysis, it adds cognitive overload, it opens up potential for misuse of the features, etc, so language changes are definitely not for free. I realize that the feature was requested by someone, but I don't see any strong argument for adding it, I see that even Matz seems to be on the fence about it, and clearly some people (like me) are frustrated by the exact syntax. I don't think that's how language design is supposed to happen (there should be more research up front) and that's definitely not a recipe for (universal) programmer happiness. The Unix people had it right - often "less is more". I'd rather have fewer, but very polished features, as opposed to many somewhat useful, but half-baked ones. 

> I just want to add again: nobody seems to be entirely happy. I think this is not good enough to add a feature to the language. After all we will have to live with it for decades to come

Spot on. Let's either rollback this, while there is still time, or come up with a syntax that more people would endorse. 

----------------------------------------
Misc #15723: Reconsider numbered parameters
https://bugs.ruby-lang.org/issues/15723#change-77311

* Author: sos4nt (Stefan Schler)
* Status: Feedback
* Priority: Normal
* Assignee: 
----------------------------------------
I just learned that *numbered parameters* have been merged into Ruby 2.7.0dev.

For readers not familiar with this feature: it allows you to reference block arguments solely by their *index*, e.g.

```ruby
[1, 2, 3].each { |i| puts i }

# can become

[1, 2, 3].each { puts @1 }
```

I have an issue with this new feature: I think **it encourages sloppy programming** and results in **hard to read code**.

---

The [original proposal](https://bugs.ruby-lang.org/issues/4475) was to include a special variable (or keyword) with a **readable name**, something like:

```ruby
[1, 2, 3].each { puts it }

# or

[1, 2, 3].each { puts this }
```

Granted, that looks quite lovely and it actually speaks to me  I can *understand* the code. And it fits Ruby: (quoting the website)

> [Ruby] has an elegant syntax that is natural to read and easy to write.

But the proposed `it` / `this` has limited application. It's only useful when dealing with a single argument. You can't have multiple `it`-s or `this`-es. That's why `@1`, `@2`, `@3` etc. were chosen instead.

However, limiting the usefulness to a single argument isn't bad at at. In fact, a single argument seem to be the limit of what makes sense:
```
h = Hash.new { |hash, key| hash[key] = "Go Fish: #{key}" }

# vs

h = Hash.new { @1[@2] = "Go Fish: #{@2}" }
```
Who wants to read the latter? That looks like an archaic bash program (no offense). We already discourage Perl style `$`-references: (from [The Ruby Style Guide](https://github.com/rubocop-hq/ruby-style-guide#no-perl-regexp-last-matchers))

> Don't use the cryptic Perl-legacy variables denoting last regexp group matches (`$1`, `$2`, etc). Use `Regexp.last_match(n)` instead.

I don't see how our code can benefit from adding `@1` and `@2`.

Naming a parameter isn't useless  it gives context. With more than one parameter, naming is crucial. And yes, naming is hard. But avoiding proper naming by using indices is the wrong way.

So please reconsider numbered parameters.

Use a readable named variable (or keyword) to refer to the first argument or ditch the feature entirely.



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