From: "kyanagi (Kouhei Yanagita)" Date: 2021-09-20T15:25:39+00:00 Subject: [ruby-core:105354] [Ruby master Feature#18181] Introduce Enumerable#min_with_value, max_with_value, and minmax_with_value Issue #18181 has been reported by kyanagi (Kouhei Yanagita). ---------------------------------------- Feature #18181: Introduce Enumerable#min_with_value, max_with_value, and minmax_with_value https://bugs.ruby-lang.org/issues/18181 * Author: kyanagi (Kouhei Yanagita) * Status: Open * Priority: Normal ---------------------------------------- PR is https://github.com/ruby/ruby/pull/4874 I propose `Enumerable#min_with_value`, `max_with_value` and `minmax_with_value`. These methods work like this: ``` ruby %w(abcde fg hijk).min_with_value { |e| e.size } # => ['fg', 2] %w(abcde fg hijk).max_with_value { |e| e.size } # => ['abcde', 5] %w(abcde fg hijk).minmax_with_value { |e| e.size } # => [['fg', 2], ['abcde', 5]] ``` Motivation: When I use `Enumerable#min_by`, I sometimes want to get not only the minimum element but also the value from the given block. (e.g.: There are many points. Find the nearest point and get distance to it.) ``` ruby elem = enum.min_by { |e| foo(e) } value = foo(elem) ``` This works, but I'd like to avoid writing foo() twice. (Consider a more complex case.) This can be written without repeated foo() like belows, but it is slightly complicated and needs extra arrays. ``` ruby value, elem = enum.map { |e| [foo(e), e] }.min_by(&:first) ``` If the size of enum is enormous, it is hard to use intermediate arrays. `Enumerable#min_with_value` solves this problem. I think `min_with_value` is the best name I could think of, but any suggestions for better names would be appreciated. -- https://bugs.ruby-lang.org/ Unsubscribe: