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Issue #9453 has been updated by Vais Salikhov.
`attr_*` methods returning `nil` should be considered a bug at this point, since all other ways of defining methods return a symbol. This makes Ruby inconsistent, and violates its own Principle of Least Surprise.
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Feature #9453: Return symbols of defined methods for `attr` and friends
https://bugs.ruby-lang.org/issues/9453#change-63426
* Author: Joshua Ballanco
* Status: Rejected
* Priority: Normal
* Assignee: Yukihiro Matsumoto
* Target version:
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With Ruby 2.1 returning a symbol from `def` and `define_method`, that leaves `attr`, `attr_reader`, `attr_writer`, and `attr_accessor` as ways to define methods that still return nil. This is unfortunate, because it prevents the use of method decorators developed to work with `def` from also working with the `attr*` methods. Because these mechanisms can define more than one method, the return values would need to be arrays of symbols.
For an example of how this could be useful in real-world code, consider this sample from James Edward Gray II's Warehouse Keeper example (https://github.com/JEG2/warehouse_keeper):
attr_reader :images, :key_map, :window, :screen_manager, :animations
private :images, :key_map, :window, :screen_manager, :animations
if `attr_reader` returned symbols, then this could be simplified to:
private *attr_reader(:images, :key_map, :window, :screen_manager, :animations)
I've attached a patch that implements this change and includes a few tests. For those who use git, I've also submitted this as a pull request here: https://github.com/ruby/ruby/pull/517
---Files--------------------------------
attr_rv.patch (3.23 KB)
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