From: eregontp@... Date: 2019-04-09T19:41:44+00:00 Subject: [ruby-core:92222] [Ruby trunk Bug#15708] Implicit numbered argument decomposes an array Issue #15708 has been updated by Eregon (Benoit Daloze). For some reason, a reply on the tracker seems to have been lost, or removed. I think it is highly relevant, so I'll quote it here: sholden (Scott Holden) wrote: > This is definitely not the behavior I would expect. In everything that I've seen, developers are describing the feature such that > > ``` ruby > a.map{|x| x} == a.map{ @1 } > ``` > > This would be a very surprising behavior for people to stumble upon. ---------------------------------------- Bug #15708: Implicit numbered argument decomposes an array https://bugs.ruby-lang.org/issues/15708#change-77559 * Author: sawa (Tsuyoshi Sawada) * Status: Open * Priority: Normal * Assignee: * Target version: * ruby -v: 2.7.0dev * Backport: 2.4: UNKNOWN, 2.5: UNKNOWN, 2.6: UNKNOWN ---------------------------------------- In the following, `@1` refers to the entire item iterated: ```ruby a = [1, 2, 3] a.map{|x| x} # => [1, 2, 3] a.map{@1} # => [1, 2, 3] ``` whereas in the following, `@1` refers to the first item achieved by decomposing the item iterated, behaving the same as `x` given by `|(x)|` rather than by `|x|`: ```ruby a = [[1], [2], [3]] a.map{|x| x} # => [[1], [2], [3]] a.map{|(x)| x} # => [1, 2, 3] a.map{@1} # => [1, 2, 3] ``` Is this intended? -- https://bugs.ruby-lang.org/ Unsubscribe: