From: naruse@... Date: 2017-10-19T08:58:16+00:00 Subject: [ruby-core:83389] [Ruby trunk Feature#8948] Frozen regex Issue #8948 has been updated by naruse (Yui NARUSE). This change will break compatibility. If the change has clear benefit, such incompatibility is acceptable. But this benefit seems not so much. If so this should be postponed on introducing parallelization. ---------------------------------------- Feature #8948: Frozen regex https://bugs.ruby-lang.org/issues/8948#change-67350 * Author: sawa (Tsuyoshi Sawada) * Status: Assigned * Priority: Normal * Assignee: matz (Yukihiro Matsumoto) * Target version: ---------------------------------------- =begin I see that frozen string was accepted for Ruby 2.1, and frozen array and hash are proposed in https://bugs.ruby-lang.org/issues/8909. I feel there is even more use case for a frozen regex, i.e., a regex literal that generates a regex only once. It is frequent to have a regex within a frequently repeated portion of code, and generating the same regex each time is a waste of resource. At the moment, we can have a code like: class Foo RE1 = /pattern1/ RE2 = /pattern1/ RE3 = /pattern1/ def classify case self when RE1 then 1 when RE2 then 2 when RE3 then 3 else 4 end end end but suppose we have a frozen `Regexp` literal `//f`. Then we can write like: class Foo def classify case self when /pattern1/f then 1 when /pattern1/f then 2 when /pattern1/f then 3 else 4 end end end =end -- https://bugs.ruby-lang.org/ Unsubscribe: