From: "mame (Yusuke Endoh)" Date: 2012-03-30T02:17:44+09:00 Subject: [ruby-core:43894] [ruby-trunk - Feature #6166][Assigned] Enumerator::Lazy#pinch Issue #6166 has been updated by mame (Yusuke Endoh). Status changed from Open to Assigned Assignee set to matz (Yukihiro Matsumoto) Hello, If this kind of operations occur frequently, I think it is worth to add a method. But I'm not sure because Lazy just entered trunk. My current opinion. I like this style: e.lazy.pinch(1, 2) == e.lazy.drop(1).first(2) because it is: - more explicit than pinch - more efficient than to_a[1, 2] (when e is very long) -- Yusuke Endoh ---------------------------------------- Feature #6166: Enumerator::Lazy#pinch https://bugs.ruby-lang.org/issues/6166#change-25405 Author: trans (Thomas Sawyer) Status: Assigned Priority: Normal Assignee: matz (Yukihiro Matsumoto) Category: core Target version: In previous issue #6158 it has been determined that Enumerator::Lazy#take should be lazy. But an eager form of #take would still be useful. To this end I'll suggest `Enumerator::Lazy#pinch`. Examples of usage: e.lazy.pinch 1 e.lazy.pinch 1..2 e.lazy.pinch 1,2 It is basically equivalent to calling `to_a[index]`, but has the advantage of being a single invocation instead of two, and reads better. The #pinch method would be strictly a Lazy method and have no counterpart in Enumerable. -- http://bugs.ruby-lang.org/