From: matz@... Date: 2020-10-03T08:14:20+00:00 Subject: [ruby-core:100289] [Ruby master Bug#17178] Procs with kw:def/**kw lose elements when called with a single Array Issue #17178 has been updated by matz (Yukihiro Matsumoto). Status changed from Open to Closed I think it should be as it is. It would break compatibility from Ruby2.x. It's not that big issue worh breaking. Matz. ---------------------------------------- Bug #17178: Procs with kw:def/**kw lose elements when called with a single Array https://bugs.ruby-lang.org/issues/17178#change-87874 * Author: Eregon (Benoit Daloze) * Status: Closed * Priority: Normal * Assignee: matz (Yukihiro Matsumoto) * ruby -v: ruby 3.0.0dev (2020-09-18T09:12:58Z master e1cca08a6d) [x86_64-linux] * Backport: 2.5: UNKNOWN, 2.6: UNKNOWN, 2.7: UNKNOWN ---------------------------------------- ``` $ ruby -ve '{a: 1}.each_pair { |a, kw: :def| p [a,kw] }' ruby 3.0.0dev (2020-09-18T09:12:58Z master e1cca08a6d) [x86_64-linux] [:a, :def] # bug, should be [[1, 2], :def] $ ruby -ve '{a: 1}.each_pair { |a, **kw| p [a,kw] }' ruby 3.0.0dev (2020-09-18T09:12:58Z master e1cca08a6d) [x86_64-linux] [:a, {}] # bug, should be [[1, 2], {}] ``` So the value of the key-value pair is lost and not assigned to any argument. This seems a general problem of Proc, not just #each_pair: ``` $ ruby -e 'proc { |a, kw: :def| p [a,kw] }.call(1,2)' [1, :def] # understandable $ ruby -e 'proc { |a, kw: :def| p [a,kw] }.call([1,2])' [1, :def] # bug, should be [[1, 2], :def] $ ruby -e 'proc { |a, **kw| p [a,kw] }.call(1,2)' [1, {}] # understandable $ ruby -e 'proc { |a, **kw| p [a,kw] }.call([1,2])' [1, {}] # bug, should be [[1, 2], {}] ``` -- https://bugs.ruby-lang.org/ Unsubscribe: