< :前の番号
^ :番号順リスト
> :次の番号
P :前の記事（スレッド移動）
N :次の記事（スレッド移動）
|<:前のスレッド
>|:次のスレッド
^ :返事先
_:自分への返事
>:同じ返事先を持つ記事（前）
<:同じ返事先を持つ記事（後）
---:分割してスレッド表示、再表示
| :分割して（縦）スレッド表示、再表示
~ :スレッドのフレーム消去
.:インデックス
..:インデックスのインデックス
Issue #18242 has been updated by nobu (Nobuyoshi Nakada).
That patch seems not including `1 < 2 and a = 1, 2`.
https://github.com/ruby/ruby/pull/4945
----------------------------------------
Feature #18242: Parser makes multiple assignment sad in confusing way
https://bugs.ruby-lang.org/issues/18242#change-94061
* Author: danh337 (Dan H)
* Status: Open
* Priority: Normal
----------------------------------------
Example:
``` ruby
a, b = 2, 1 if 1 < 2 # Works
a, b = [2, 1] if 1 < 2 # Works
(a, b) = 2, 1 if 1 < 2 # Works
(a, b) = [2, 1] if 1 < 2 # Works
(a, b = [2, 1]) if 1 < 2 # Works
a, b = 2, 1 unless 2 < 1 # Works
a, b = [2, 1] unless 2 < 1 # Works
(a, b) = 2, 1 unless 2 < 1 # Works
(a, b) = [2, 1] unless 2 < 1 # Works
(a, b = [2, 1]) unless 2 < 1 # Works
1 < 2 and a, b = 2, 1 # SyntaxError
1 < 2 and a, b = [2, 1] # SyntaxError
1 < 2 and (a, b) = 2, 1 # SyntaxError
1 < 2 and (a, b) = [2, 1] # SyntaxError
(1 < 2) and a, b = 2, 1 # SyntaxError
(1 < 2) and a, b = [2, 1] # SyntaxError
(1 < 2) and (a, b) = 2, 1 # SyntaxError
(1 < 2) and (a, b) = [2, 1] # SyntaxError
1 < 2 and (a, b = 2, 1) # Works
1 < 2 and (a, b = [2, 1]) # Works
2 < 1 or a, b = 2, 1 # SyntaxError
2 < 1 or a, b = [2, 1] # SyntaxError
2 < 1 or (a, b) = 2, 1 # SyntaxError
2 < 1 or (a, b) = [2, 1] # SyntaxError
(2 < 1) or a, b = 2, 1 # SyntaxError
(2 < 1) or a, b = [2, 1] # SyntaxError
(2 < 1) or (a, b) = 2, 1 # SyntaxError
(2 < 1) or (a, b) = [2, 1] # SyntaxError
2 < 1 or (a, b = 2, 1) # Works
2 < 1 or (a, b = [2, 1]) # Works
```
Based on the precedence rules I've been able to find, all of these should work.
Believe it or not, there are cases where using `and` or `or` in a stanza of lines is much more readable.
Should the parser allow all of these? See attached driver script to reproduce this output.
---Files--------------------------------
driver.rb (1.17 KB)
and-or-masgn-18242.diff (963 Bytes)
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