From: "austin (Austin Ziegler)" <noreply@...>
Date: 2022-09-28T14:32:21+00:00
Subject: [ruby-core:110126] [Ruby master Feature#19027] .= syntax

Issue #19027 has been updated by austin (Austin Ziegler).


jeromedalbert (Jerome Dalbert) wrote:
> I wish I could do this in Ruby:
> 
> ```
> records .= where.not(id: excluded_ids) if some_condition
> ```
> 
> instead of:
> 
> ```
> records = records.where.not(id: excluded_ids) if some_condition
> ```
 
I find that both unreadable and undecipherable, personally. This is one case where something like a pipeline operator might be better (https://bugs.ruby-lang.org/issues/15799).

```ruby
records =
  RecordSource
  |> where(���) # original condition
  |> maybe_exclude(some_condition, excluded_ids)

���

def maybe_exclude(records, condition, excluded_ids)
  condition ? records.where.not(id: excluded_ids) : records
end
```

It���s not *shorter*, but it allows for a better reading of the query build in the first place. It might be possible to do something like that using `Kernel#then`:

```ruby
records =
  RecordSource
    .where(���) # original condition
    .then { maybe_exclude(_1, some_condition, excluded_ids) }

���

def maybe_exclude(records, condition, excluded_ids)
  condition ? records.where.not(id: excluded_ids) : records
end
```

> We already have `+=`, `-=`, `||=`, etc, so why not have a `.=` syntax?

This would be different than the others, because `+=` &c. result in method calls on the receiver. If we wanted something clearer, maybe `records = &..when.not���` where `&..` would be a signal to "retrieve the previous variable symbol to use here".

----------------------------------------
Feature #19027: .= syntax
https://bugs.ruby-lang.org/issues/19027#change-99384

* Author: jeromedalbert (Jerome Dalbert)
* Status: Rejected
* Priority: Normal
----------------------------------------
I wish I could do this in Ruby:

```
records .= where.not(id: excluded_ids) if some_condition
```

instead of:

```
records = records.where.not(id: excluded_ids) if some_condition
```

We already have `+=`, `-=`, `||=`, etc, so why not have a `.=` syntax?

I rarely need this since most of the time self replacement methods like `gsub!` are available. Over my many years of Ruby programming I wished I could use a `.=` syntax maybe a handful of times, so this would be a rarely useful feature, but I find it to be quite elegant in the rare cases it could be needed.

Maybe this is just me being weird but I thought I would share.



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