[ruby-core:121065] [Ruby master Feature#16993] Sets: from hash keys using Hash#key_set
From:
"nobu (Nobuyoshi Nakada) via ruby-core" <ruby-core@...>
Date:
2025-02-15 04:07:25 UTC
List:
ruby-core #121065
Issue #16993 has been updated by nobu (Nobuyoshi Nakada).
This kind of extensions should be done in the corresponding library side, set.rb.
----------------------------------------
Feature #16993: Sets: from hash keys using Hash#key_set
https://bugs.ruby-lang.org/issues/16993#change-111978
* Author: marcandre (Marc-Andre Lafortune)
* Status: Open
----------------------------------------
To create a set from hash keys currently implies a temporary array for all keys, rehashing all those keys and rebuilding a hash. Instead, the hash could be copied and its values set to `true`.
```ruby
h = {a: 1}
# Now:
Set.new(h.keys) # => Set[:a]
# After
h.key_set # => Set[:a], efficiently.
```
--
https://bugs.ruby-lang.org/
______________________________________________
ruby-core mailing list -- ruby-core@ml.ruby-lang.org
To unsubscribe send an email to ruby-core-leave@ml.ruby-lang.org
ruby-core info -- https://ml.ruby-lang.org/mailman3/lists/ruby-core.ml.ruby-lang.org/