From: kaspth@... Date: 2016-12-22T19:36:44+00:00 Subject: [ruby-core:78806] [Ruby trunk Feature#12979] Avoid exception for #dup on Integer (and similar cases) Issue #12979 has been updated by Kasper Timm Hansen. In Rails we've circumvented this with a `duplicable?` core extension. We'd need `dup` support on Method, Complex and Rational too remove it entirely: https://github.com/rails/rails/blob/fd63aa02289d64e9d14fe56723f1de64bca3bb1f/activesupport/lib/active_support/core_ext/object/duplicable.rb#L115-L143 Would that be possible too? Thanks :) ---------------------------------------- Feature #12979: Avoid exception for #dup on Integer (and similar cases) https://bugs.ruby-lang.org/issues/12979#change-62213 * Author: Martin D��rst * Status: Closed * Priority: Normal * Assignee: Nobuyoshi Nakada * Target version: ---------------------------------------- This is a proposal resulting from a discussion in Bug #11929. Because this is proposing a different solution from #11929, it has a new number. #11929 shows that people are confused that e.g. 3.dup throws an exception (but Integer#dup is actually implemented, so Integer.respond_to? :dup => true). Integer#dup should fail silently, returning the receiver, in the same way as Integer#freeze fails silently. Citing from #11929 (comment by Mike Vastola): "If the object can't be duped/cloned because it's an immediate, dup/clone should return the object itself. (There shouldn't be any harm in doing so since nothing about the object can be changed in the first place.)". Citing some more: > I literally can't imagine any scenario in which a dev, when, say, coding a class with the line: > > return val.dup.freeze > .. really wants an Exception thrown when val happens to be de-facto un-dup-able. What they really want is: > > return val.dup.freeze rescue val The proposal also has the advantage that it leads to a much more unified, streamlined protocol, avoiding needless exposition of internals. It would do exactly what dup (and clone) are described to do, namely (pretend to) return a shallow copy. -- https://bugs.ruby-lang.org/ Unsubscribe: