* [ruby-core:94101] [Ruby master Feature#16035] Allow non-finalizable objects such as Integer, static Symbol etc in ObjectSpace::WeakMap
[not found] <redmine.issue-16035.20190801190200@ruby-lang.org>
@ 2019-08-01 19:02 ` jean.boussier
2019-08-29 6:31 ` [ruby-core:94648] " ko1
` (2 subsequent siblings)
3 siblings, 0 replies; 4+ messages in thread
From: jean.boussier @ 2019-08-01 19:02 UTC (permalink / raw
To: ruby-core
Issue #16035 has been reported by byroot (Jean Boussier).
----------------------------------------
Feature #16035: Allow non-finalizable objects such as Integer, static Symbol etc in ObjectSpace::WeakMap
https://bugs.ruby-lang.org/issues/16035
* Author: byroot (Jean Boussier)
* Status: Open
* Priority: Normal
* Assignee:
* Target version:
----------------------------------------
This goes one step farther than what @nobu did in https://bugs.ruby-lang.org/issues/13498
With this patch, special objects such as static symbols, integers, etc can be used as either key or values inside WeakMap. They simply don't have a finalizer defined on them.
This is useful if you need to deduplicate value objects, e.g. some minimal use case:
```ruby
class Money
REGISTRY = ObjectSpace::WeakMap.new
private_constant :REGISTRY
def self.new(amount)
REGISTRY[amount] ||= super.freeze
end
def initialize(amount)
@amount = amount
end
end
if Money.new(42).eql?(Money.new(42))
puts "Same instance"
else
puts "Different instances"
end
```
This is a very simple example, but more complex examples can create use a dynamically created symbol as deduplication key, etc.
It also removes one weirdness introduced in the mentioned patch:
```ruby
wmap = ObjectSpace::WeakMap.new
wmap["foo".to_sym] = Object.new # works fine with dynamic symbols
wmap[:bar] = Object.new # cannot define finalizer for Symbol (ArgumentError)
```
Proposed patch: https://github.com/ruby/ruby/pull/2313
--
https://bugs.ruby-lang.org/
^ permalink raw reply [flat|nested] 4+ messages in thread
* [ruby-core:94648] [Ruby master Feature#16035] Allow non-finalizable objects such as Integer, static Symbol etc in ObjectSpace::WeakMap
[not found] <redmine.issue-16035.20190801190200@ruby-lang.org>
2019-08-01 19:02 ` [ruby-core:94101] [Ruby master Feature#16035] Allow non-finalizable objects such as Integer, static Symbol etc in ObjectSpace::WeakMap jean.boussier
@ 2019-08-29 6:31 ` ko1
2019-08-29 6:41 ` [ruby-core:94649] " ko1
2019-08-29 6:44 ` [ruby-core:94650] " matz
3 siblings, 0 replies; 4+ messages in thread
From: ko1 @ 2019-08-29 6:31 UTC (permalink / raw
To: ruby-core
Issue #16035 has been updated by ko1 (Koichi Sasada).
`42` never be collected. Is it intentional?
----------------------------------------
Feature #16035: Allow non-finalizable objects such as Integer, static Symbol etc in ObjectSpace::WeakMap
https://bugs.ruby-lang.org/issues/16035#change-81246
* Author: byroot (Jean Boussier)
* Status: Open
* Priority: Normal
* Assignee:
* Target version:
----------------------------------------
This goes one step farther than what @nobu did in https://bugs.ruby-lang.org/issues/13498
With this patch, special objects such as static symbols, integers, etc can be used as either key or values inside WeakMap. They simply don't have a finalizer defined on them.
This is useful if you need to deduplicate value objects, e.g. some minimal use case:
```ruby
class Money
REGISTRY = ObjectSpace::WeakMap.new
private_constant :REGISTRY
def self.new(amount)
REGISTRY[amount] ||= super.freeze
end
def initialize(amount)
@amount = amount
end
end
if Money.new(42).eql?(Money.new(42))
puts "Same instance"
else
puts "Different instances"
end
```
This is a very simple example, but more complex examples can create use a dynamically created symbol as deduplication key, etc.
It also removes one weirdness introduced in the mentioned patch:
```ruby
wmap = ObjectSpace::WeakMap.new
wmap["foo".to_sym] = Object.new # works fine with dynamic symbols
wmap[:bar] = Object.new # cannot define finalizer for Symbol (ArgumentError)
```
Proposed patch: https://github.com/ruby/ruby/pull/2313
--
https://bugs.ruby-lang.org/
^ permalink raw reply [flat|nested] 4+ messages in thread
* [ruby-core:94649] [Ruby master Feature#16035] Allow non-finalizable objects such as Integer, static Symbol etc in ObjectSpace::WeakMap
[not found] <redmine.issue-16035.20190801190200@ruby-lang.org>
2019-08-01 19:02 ` [ruby-core:94101] [Ruby master Feature#16035] Allow non-finalizable objects such as Integer, static Symbol etc in ObjectSpace::WeakMap jean.boussier
2019-08-29 6:31 ` [ruby-core:94648] " ko1
@ 2019-08-29 6:41 ` ko1
2019-08-29 6:44 ` [ruby-core:94650] " matz
3 siblings, 0 replies; 4+ messages in thread
From: ko1 @ 2019-08-29 6:41 UTC (permalink / raw
To: ruby-core
Issue #16035 has been updated by ko1 (Koichi Sasada).
Assignee set to nobu (Nobuyoshi Nakada)
Status changed from Feedback to Assigned
sorry, value is collectable (my misunderstand).
----------------------------------------
Feature #16035: Allow non-finalizable objects such as Integer, static Symbol etc in ObjectSpace::WeakMap
https://bugs.ruby-lang.org/issues/16035#change-81248
* Author: byroot (Jean Boussier)
* Status: Assigned
* Priority: Normal
* Assignee: nobu (Nobuyoshi Nakada)
* Target version:
----------------------------------------
This goes one step farther than what @nobu did in https://bugs.ruby-lang.org/issues/13498
With this patch, special objects such as static symbols, integers, etc can be used as either key or values inside WeakMap. They simply don't have a finalizer defined on them.
This is useful if you need to deduplicate value objects, e.g. some minimal use case:
```ruby
class Money
REGISTRY = ObjectSpace::WeakMap.new
private_constant :REGISTRY
def self.new(amount)
REGISTRY[amount] ||= super.freeze
end
def initialize(amount)
@amount = amount
end
end
if Money.new(42).eql?(Money.new(42))
puts "Same instance"
else
puts "Different instances"
end
```
This is a very simple example, but more complex examples can create use a dynamically created symbol as deduplication key, etc.
It also removes one weirdness introduced in the mentioned patch:
```ruby
wmap = ObjectSpace::WeakMap.new
wmap["foo".to_sym] = Object.new # works fine with dynamic symbols
wmap[:bar] = Object.new # cannot define finalizer for Symbol (ArgumentError)
```
Proposed patch: https://github.com/ruby/ruby/pull/2313
--
https://bugs.ruby-lang.org/
^ permalink raw reply [flat|nested] 4+ messages in thread
* [ruby-core:94650] [Ruby master Feature#16035] Allow non-finalizable objects such as Integer, static Symbol etc in ObjectSpace::WeakMap
[not found] <redmine.issue-16035.20190801190200@ruby-lang.org>
` (2 preceding siblings ...)
2019-08-29 6:41 ` [ruby-core:94649] " ko1
@ 2019-08-29 6:44 ` matz
3 siblings, 0 replies; 4+ messages in thread
From: matz @ 2019-08-29 6:44 UTC (permalink / raw
To: ruby-core
Issue #16035 has been updated by matz (Yukihiro Matsumoto).
I think this is the required behavior for `WeakMap` to implement a cache for example. Accepted.
Matz.
----------------------------------------
Feature #16035: Allow non-finalizable objects such as Integer, static Symbol etc in ObjectSpace::WeakMap
https://bugs.ruby-lang.org/issues/16035#change-81249
* Author: byroot (Jean Boussier)
* Status: Assigned
* Priority: Normal
* Assignee: nobu (Nobuyoshi Nakada)
* Target version:
----------------------------------------
This goes one step farther than what @nobu did in https://bugs.ruby-lang.org/issues/13498
With this patch, special objects such as static symbols, integers, etc can be used as either key or values inside WeakMap. They simply don't have a finalizer defined on them.
This is useful if you need to deduplicate value objects, e.g. some minimal use case:
```ruby
class Money
REGISTRY = ObjectSpace::WeakMap.new
private_constant :REGISTRY
def self.new(amount)
REGISTRY[amount] ||= super.freeze
end
def initialize(amount)
@amount = amount
end
end
if Money.new(42).eql?(Money.new(42))
puts "Same instance"
else
puts "Different instances"
end
```
This is a very simple example, but more complex examples can create use a dynamically created symbol as deduplication key, etc.
It also removes one weirdness introduced in the mentioned patch:
```ruby
wmap = ObjectSpace::WeakMap.new
wmap["foo".to_sym] = Object.new # works fine with dynamic symbols
wmap[:bar] = Object.new # cannot define finalizer for Symbol (ArgumentError)
```
Proposed patch: https://github.com/ruby/ruby/pull/2313
--
https://bugs.ruby-lang.org/
^ permalink raw reply [flat|nested] 4+ messages in thread
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2019-08-01 19:02 ` [ruby-core:94101] [Ruby master Feature#16035] Allow non-finalizable objects such as Integer, static Symbol etc in ObjectSpace::WeakMap jean.boussier
2019-08-29 6:31 ` [ruby-core:94648] " ko1
2019-08-29 6:41 ` [ruby-core:94649] " ko1
2019-08-29 6:44 ` [ruby-core:94650] " matz
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