From: ruby-core@... Date: 2016-03-17T18:17:24+00:00 Subject: [ruby-core:74437] [Ruby trunk Bug#11816] Partial safe navigation operator Issue #11816 has been updated by Marc-Andre Lafortune. I feel that `a&.b.c += d` is still an assignment, so should be treated with the same precedence. a = nil a&.b.c += d # => nil a&.b.c ||= d # => nil a&.b.c &&= d # => nil # etc... I think this is the most helpful solution. Moreover, we already have (in 2.3.0) a&.b += d # => nil a&.b ||= d # => nil a&.b &&= d # => nil Given this, I feel the resolution I'm giving is also the most intuitive. Just to be sure, with "propagating &. as long as explicit method chain continues", we consider that `x&.foo * 42` returns `nil`, as calling `*` is equivalent to `.*`, right? ---------------------------------------- Bug #11816: Partial safe navigation operator https://bugs.ruby-lang.org/issues/11816#change-57556 * Author: Marc-Andre Lafortune * Status: Open * Priority: Normal * Assignee: Yukihiro Matsumoto * ruby -v: preview 2 * Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN ---------------------------------------- I'm extremely surprised (and disappointed) that, currently: x = nil x&.foo.bar # => NoMethodError: undefined method `bar' for nil:NilClass To make it safe, you have to write `x&.foo&.bar`. But if `foo` is never supposed to return `nil`, then that code isn't "fail early" in case it actually does. `nil&.foo.bar` is more expressive, simpler and is perfect if you want to an error if `foo` returned `nil`. To actually get what you want, you have to resort using the old form `x && x.foo.bar`... In CoffeeScript, you can write `x()?.foo.bar` and it will work well, since it gets compiled to if ((_ref = x()) != null) { _ref.foo.bar; } All the discussion in #11537 focuses on `x&.foo&.bar`, so I have to ask: Matz, what is your understanding of `x&.foo.bar`? I feel the current implementation is not useful and should be changed to what I had in mind. I can't see any legitimate use of `x&.foo.bar` currently. -- https://bugs.ruby-lang.org/ Unsubscribe: