From: "Earlopain (Earlopain _) via ruby-core" <ruby-core@...>
Date: 2026-02-27T11:08:18+00:00
Subject: [ruby-core:124890] [Ruby Bug#21927] Prism: misleading error message for forwarding in lambda argument

Issue #21927 has been updated by Earlopain (Earlopain _).


https://github.com/ruby/prism/pull/3947

----------------------------------------
Bug #21927: Prism: misleading error message for forwarding in lambda argument
https://bugs.ruby-lang.org/issues/21927#change-116549

* Author: nobu (Nobuyoshi Nakada)
* Status: Open
* Assignee: prism
* ruby -v: d256629bf9
* Backport: 3.2: DONTNEED, 3.3: DONTNEED, 3.4: REQUIRED, 4.0: REQUIRED
----------------------------------------
Even in a forwarding method:

```console
$ ruby --parser=prism -e 'def m(...) ->(...){}; end'
-e: -e:1: syntax error found (SyntaxError)
> 1 | def m(...) ->(...){}; end
    |               ^~~ unexpected ... when the parent method is not forwarding
```

This message is proper for method arguments:

```console
$ ruby --parser=prism -e 'def m() p(...); end'
-e: -e:1: syntax error found (SyntaxError)
> 1 | def m() p(...); end
    |           ^~~ unexpected ... when the parent method is not forwarding
```

The message from parse.y is different; "unexpected ... in lambda argument":
```console
$ ruby --parser=parse.y -e 'def m(...) ->(...){}; end'
-e:1: unexpected ... in lambda argument
def m(...) ->(...){}; end
ruby: compile error (SyntaxError)
```



-- 
https://bugs.ruby-lang.org/
______________________________________________
 ruby-core mailing list -- ruby-core@ml.ruby-lang.org
 To unsubscribe send an email to ruby-core-leave@ml.ruby-lang.org
 ruby-core info -- https://ml.ruby-lang.org/mailman3/lists/ruby-core.ml.ruby-lang.org/