Issue #20952 has been updated by eightbitraptor (Matt V-H). Status changed from Closed to Open Re-Opening this in light of @jeremyevans0 comment about blocks I merged the PR that addresses the kwargs issue at the same time as that comment was made. ---------------------------------------- Bug #20952: A weird error message for []= with keyword arguments https://bugs.ruby-lang.org/issues/20952#change-111002 * Author: zverok (Victor Shepelev) * Status: Open * Backport: 3.1: DONTNEED, 3.2: DONTNEED, 3.3: DONTNEED ---------------------------------------- Trying to document the new deprecation of `#[]=` with keyword arguments, I wrote this sample code: ```ruby class MyMatrix # ...some implementation def []=(*args, **kwargs) p(args:, kwargs:) # ...some implementation end end matrix = MyMatrix.new matrix[5, axis: :y] = 8 ``` This fails as expected, but the error message is totally unexpected for me: ``` ruby3_4.rb:11:in '<main>': undefined method '[]=' for an instance of Integer (NoMethodError) matrix[5, axis: :y] = 8 ^^^^^^^^^^^^^^^ ``` Am I missing some interpretation peculiarity here?.. ``` $ ruby -v ruby 3.4.0dev (2024-12-11T19:50:20Z master 34e68548d4) +PRISM [x86_64-linux] ``` -- https://bugs.ruby-lang.org/