Feature #8906


Freeze Symbols

Added by ko1 (Koichi Sasada) about 9 years ago. Updated about 9 years ago.

Target version:


Now, Integer and Float objects are frozen objects.
How about to freeze Symbol objects, too?
I think Symbol is friend of Integer.

Current behavior:
p :foo.frozen? #=> false
:foo.instance_variable_set(:@foo, 1)
p :foo.instance_variable_get(:@foo) #=> 1

Background of this proposal:

Now, I'm working on "GC-able Symbols" feature.
Freezing symbols make this feature easier.

for example:
(1) set an instance variable @iv for symbol s
(2) collect s
(3) generate s
(4) what value of @iv for s returns?

Related issues 1 (0 open1 closed)

Related to Ruby master - Feature #8579: Frozen string syntaxClosedcharliesome (Charlie Somerville)06/29/2013Actions

Updated by matz (Yukihiro Matsumoto) about 9 years ago

Symbol is a symbol is a symbol. It's not a string, nor an integer.

Besides that, I agree with making symbols frozen.


Updated by headius (Charles Nutter) about 9 years ago

+1. Anything that can't be extended and whose regular state can't be mutated (not counting user-provided instance vars and such) should be frozen.

Updated by Anonymous about 9 years ago

Cool, I love frozen stuff!

Actions #4

Updated by ko1 (Koichi Sasada) about 9 years ago

  • Status changed from Open to Closed
  • % Done changed from 0 to 100

This issue was solved with changeset r42974.
Koichi, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.

  • include/ruby/ruby.h: make Symbol objects frozen.
    [Feature #8906]
    I want to freeze this good day, too.
  • test/ruby/test_eval.rb: catch up this change.
  • test/ruby/test_symbol.rb: add a test to check frozen symbols.

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