From: frederick.cheung@... Date: 2019-07-02T21:05:36+00:00 Subject: [ruby-core:93504] [Ruby master Feature#15976] Add Array#overlap? for whether the intersection of 2 arrays is non empty? Issue #15976 has been updated by fcheung (Frederick Cheung). shevegen (Robert A. Heiler) wrote: > To me the name of the method appears to make sense and I am slightly in > favour of the suggestion. I can not say how useful this method would be > in general, though, mostly because I think I needed to do something > such as (array1 & array2).any? perhaps only once or twice in a long > time in my own code; but even then I think this might be a useful > proposal and a name that makes sense (to me at the least). Thanks. Matz suggested today that the name was not so clear to him. An alternative that springs to mind would be `intersect?`, but I am obviously open to any suggestions ---------------------------------------- Feature #15976: Add Array#overlap? for whether the intersection of 2 arrays is non empty? https://bugs.ruby-lang.org/issues/15976#change-79064 * Author: fcheung (Frederick Cheung) * Status: Open * Priority: Normal * Assignee: * Target version: ---------------------------------------- This is semantically equivalent to `(ary1 & ary2).any?`, but more efficient and makes the intent more obvious. For example bundler [checks]( https://github.com/ruby/ruby/blob/master/lib/bundler/runtime.rb#L61 ) whether the list of requested groups and the list of groups for a dependency has any overlap - it doesn't care what the overlap is, as long as it is non empty In my personal projects we've found this to be a bottleneck when the arrays are large and where intersections are likely - `!(ary1 & ary2).empty?` keeps searching for all of the intersection even after we've found the first one, & creates extra garbage because of the intermediate array. See https://github.com/ruby/ruby/pull/2260 ---Files-------------------------------- 2260.patch (7.9 KB) -- https://bugs.ruby-lang.org/ Unsubscribe: