Issue #21168 has been updated by tenderlovemaking (Aaron Patterson). Assignee set to prism ---------------------------------------- Bug #21168: Prism doesn't require argument parentheses (in some cases) when a block is present but parse.y does https://bugs.ruby-lang.org/issues/21168#change-112184 * Author: Earlopain (Earlopain _) * Status: Open * Assignee: prism * ruby -v: ruby 3.4.2 (2025-02-15 revision d2930f8e7a) +PRISM [x86_64-linux] * Backport: 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- It's a bit more than that but explaining it in full would be a bit much. Instead, see this: ```rb foo( bar baz do end ) ``` ```sh $ ruby -c --parser=prism test.rb Syntax OK $ ruby -c --parser=parse.y test.rb ruby: test.rb:2: syntax error, unexpected 'do' for block, expecting ')' (SyntaxError) bar baz do ^~ ``` OTOH, this is consistently rejected: ```rb [ foo bar do end, ] # And also foo || bar baz do end ``` -- https://bugs.ruby-lang.org/