digitalmars.D.announce - =?UTF-8?B?U21hcnRSZWbvvJo=?= The Smart Pointer In D
- Dsby (6/6) Jan 13 2017 I write the ref count pointer and the scoped point in D.
- nbro (2/8) Jan 13 2017 What's would be the advantages of smart pointers in D?
- Swoorup Joshi (2/10) Jan 13 2017 Simple, Same Advantages you would get with C++ smart pointers.
- Dmitry Olshansky (8/19) Jan 14 2017 Not quite true, there is at least one huge advantage - thread-locality.
- Martin Nowak (3/6) Jan 14 2017 And you can add a shared postblit overload for when it's not thread
- Ola Fosheim =?UTF-8?B?R3LDuHN0YWQ=?= (11/14) Jan 23 2017 I assume you mean std::shared_ptr. The reference counting
- Chris Wright (7/16) Jan 13 2017 It's reference counting.
- nbro (4/12) Jan 14 2017 Garbage collection in D is more expensive just because of the
- Chris Wright (10/13) Jan 14 2017 I posted about this in general.
- =?UTF-8?B?Tm9yZGzDtnc=?= (7/8) Jan 14 2017 How do two of these differ from
- Dsby (11/19) Jan 15 2017 The RefCount not support class or inteface, and the ref count is
- Dsby (15/39) Jan 15 2017 Sorry,In the new phobos, THe Unique is not used the 'delete'
- Aedt (2/8) May 29 2018 Very nice. Do you have a dub package for this?
- Martin Nowak (2/5) Jun 08 2018 I hope you know https://code.dlang.org/packages/automem.
I write the ref count pointer and the scoped point in D. it just Like cpp's shared_ptr ， waek_ptr and unique_ptr . Now, it is Developing. I will write more test before the frist release. And the docs is null. It on github: https://github.com/huntlabs/SmartRef
Jan 13 2017
On Friday, 13 January 2017 at 16:50:37 UTC, Dsby wrote:I write the ref count pointer and the scoped point in D. it just Like cpp's shared_ptr ， waek_ptr and unique_ptr . Now, it is Developing. I will write more test before the frist release. And the docs is null. It on github: https://github.com/huntlabs/SmartRefWhat's would be the advantages of smart pointers in D?
Jan 13 2017
On Saturday, 14 January 2017 at 02:05:11 UTC, nbro wrote:On Friday, 13 January 2017 at 16:50:37 UTC, Dsby wrote:Simple, Same Advantages you would get with C++ smart pointers.I write the ref count pointer and the scoped point in D. it just Like cpp's shared_ptr ， waek_ptr and unique_ptr . Now, it is Developing. I will write more test before the frist release. And the docs is null. It on github: https://github.com/huntlabs/SmartRefWhat's would be the advantages of smart pointers in D?
Jan 13 2017
On 1/14/17 3:20 AM, Swoorup Joshi wrote:On Saturday, 14 January 2017 at 02:05:11 UTC, nbro wrote:Not quite true, there is at least one huge advantage - thread-locality. That is C++ smart_ptr has to be atomic, while its D counter part may safely be non-atomic because everything is TLS be default. Of course, there is a place for smart pointer shared across threads, but I'd personally go with message passing instead. --- Dmitry OlshanskyOn Friday, 13 January 2017 at 16:50:37 UTC, Dsby wrote:Simple, Same Advantages you would get with C++ smart pointers.I write the ref count pointer and the scoped point in D. it just Like cpp's shared_ptr ， waek_ptr and unique_ptr . Now, it is Developing. I will write more test before the frist release. And the docs is null. It on github: https://github.com/huntlabs/SmartRefWhat's would be the advantages of smart pointers in D?
Jan 14 2017
Martin Nowak <code+news.digitalmars dawg.eu> On 01/14/2017 04:41 PM, Dmitry Olshansky wrote:Not quite true, there is at least one huge advantage - thread-locality. That is C++ smart_ptr has to be atomic, while its D counter part may safely be non-atomic because everything is TLS be default.And you can add a shared postblit overload for when it's not thread local ;).
Jan 14 2017
On Saturday, 14 January 2017 at 15:41:01 UTC, Dmitry Olshansky wrote:That is C++ smart_ptr has to be atomic, while its D counter part may safely be non-atomic because everything is TLS be default.I assume you mean std::shared_ptr. The reference counting semantics are atomic, but the I don't think the compiler is required to if it provably isn't shared. There are also ways to get around it if needed (you only need atomic count when you enter or leave a context, e.g. thread). Of course, there are C++ single threaded alternatives with intrusive ref counting, which I believe is what D is going for. shared_ptr is non-intrusive (doesn't affect allocation or object types).
Jan 23 2017
On Sat, 14 Jan 2017 02:05:11 +0000, nbro wrote:On Friday, 13 January 2017 at 16:50:37 UTC, Dsby wrote:It's reference counting. Reference counting is like garbage collection, but deamortized. This is better for real-time applications. However, it adds overhead on every assignment and every variable going out of scope. In D, garbage collection is more expensive than it is in other languages, so the tradeoff is more attractive than it would be in other languages.I write the ref count pointer and the scoped point in D. it just Like cpp's shared_ptr ， waek_ptr and unique_ptr . Now, it is Developing. I will write more test before the frist release. And the docs is null. It on github: https://github.com/huntlabs/SmartRefWhat's would be the advantages of smart pointers in D?
Jan 13 2017
On Saturday, 14 January 2017 at 04:14:11 UTC, Chris Wright wrote:It's reference counting. Reference counting is like garbage collection, but deamortized. This is better for real-time applications. However, it adds overhead on every assignment and every variable going out of scope. In D, garbage collection is more expensive than it is in other languages, so the tradeoff is more attractive than it would be in other languages.Garbage collection in D is more expensive just because of the poor implementation, from what I've heard. If that's the case, people who work on it should be able to improve it over time.
Jan 14 2017
On Sat, 14 Jan 2017 11:52:34 +0000, nbro wrote:Garbage collection in D is more expensive just because of the poor implementation, from what I've heard. If that's the case, people who work on it should be able to improve it over time.I posted about this in general. A GC for Java, Python, Ruby, etc can locate type information and GC metadata for an allocation in O(1) time. D's can locate type information and GC metadata in O(log N) time in the worst case, even with the best possible implementation, and its design decisions make the worst case incredibly common. That is one of the common operations that a GC does, so it has a big performance impact. D's GC must be slower because it allows pointers to arbitrary places inside an allocation, and it strongly encourages this with array slicing.
Jan 14 2017
On Friday, 13 January 2017 at 16:50:37 UTC, Dsby wrote:I write the ref count pointer and the scoped point in D.How do two of these differ from - https://dlang.org/phobos/std_typecons.html#.RefCounted - https://dlang.org/phobos/std_typecons.html#.Unique under https://dlang.org/phobos/std_typecons.html ?
Jan 14 2017
On Saturday, 14 January 2017 at 17:35:09 UTC, Nordlöw wrote:On Friday, 13 January 2017 at 16:50:37 UTC, Dsby wrote:The RefCount not support class or inteface, and the ref count is not atomic ， it not thread safe. The Unique is base of GC. It can not nogc. And it use the 'delete' keyword , it will be deprcated(http://dlang.org/deprecate.html). The SmartRef is Base std.experimental.allocator. You can control where the memony allocator. And the smartref.sharedref use the atomic default, you alse can not use atomic。 And have the smartref.weakref with sharedref to fix circular reference.I write the ref count pointer and the scoped point in D.How do two of these differ from - https://dlang.org/phobos/std_typecons.html#.RefCounted - https://dlang.org/phobos/std_typecons.html#.Unique under https://dlang.org/phobos/std_typecons.html ?
Jan 15 2017
On Sunday, 15 January 2017 at 15:42:19 UTC, Dsby wrote:On Saturday, 14 January 2017 at 17:35:09 UTC, Nordlöw wrote:Sorry,In the new phobos, THe Unique is not used the 'delete' keyword. But , it only destroy, not free the memony. and : In https://github.com/dlang/phobos/blob/master/std/typecons.d#L147 ~this() { debug(Unique) writeln("Unique destructor of ", (_p is null)? null: _p); if (_p !is null) destroy(_p); _p = null; } if the 'T' is a struct, it will not exec the Destory function. Is it a bug?On Friday, 13 January 2017 at 16:50:37 UTC, Dsby wrote:The RefCount not support class or inteface, and the ref count is not atomic ， it not thread safe. The Unique is base of GC. It can not nogc. And it use the 'delete' keyword , it will be deprcated(http://dlang.org/deprecate.html). The SmartRef is Base std.experimental.allocator. You can control where the memony allocator. And the smartref.sharedref use the atomic default, you alse can not use atomic。 And have the smartref.weakref with sharedref to fix circular reference.I write the ref count pointer and the scoped point in D.How do two of these differ from - https://dlang.org/phobos/std_typecons.html#.RefCounted - https://dlang.org/phobos/std_typecons.html#.Unique under https://dlang.org/phobos/std_typecons.html ?
Jan 15 2017
On Sunday, 15 January 2017 at 15:56:30 UTC, Dsby wrote:and : In https://github.com/dlang/phobos/blob/master/std/typecons.d#L147 ~this() { debug(Unique) writeln("Unique destructor of ", (_p is null)? null: _p); if (_p !is null) destroy(_p); _p = null; } if the 'T' is a struct, it will not exec the Destory function. Is it a bug?What do you mean? This works for me: --- import std.stdio, std.typecons; struct Foo { ~this() { writeln("I'm destroyed"); } } void main() { Unique!Foo foo = new Foo; } // Prints "I'm destroyed" ---
Jan 15 2017
On Sunday, 15 January 2017 at 17:24:25 UTC, biozic wrote:On Sunday, 15 January 2017 at 15:56:30 UTC, Dsby wrote:the "writeln("I'm destroyed");" not run the ~this in the Unique destroy function. it run in the app exit , THe GC distroy all memony. it example can show : import std.stdio; import std.typecons; struct Foo { ~this() { writeln("I'm destroyed"); } } void fun(){ Unique!Foo foo = new Foo; writeln("exit the fun."); } void main() { fun(); writeln("exit the Main."); } It is the printf: ~/tmp rdmd ./type.d 2017年01月16日 星期一 09时50分00秒 exit the fun. exit the Main. I'm destroyed ~/tmp if you use the struct in Unique, the struct's Destory function is not run in the Unique destroy, it is also run in the GC collet. I think it is not the Unique should be.and : In https://github.com/dlang/phobos/blob/master/std/typecons.d#L147 ~this() { debug(Unique) writeln("Unique destructor of ", (_p is null)? null: _p); if (_p !is null) destroy(_p); _p = null; } if the 'T' is a struct, it will not exec the Destory function. Is it a bug?What do you mean? This works for me: --- import std.stdio, std.typecons; struct Foo { ~this() { writeln("I'm destroyed"); } } void main() { Unique!Foo foo = new Foo; } // Prints "I'm destroyed" ---
Jan 15 2017
On Monday, 16 January 2017 at 01:54:35 UTC, Dsby wrote:On Sunday, 15 January 2017 at 17:24:25 UTC, biozic wrote:Right, good point. This behaviour is indeed caused by destroy() and is not specific to Unique. But it the case of Unique, relying on this (undefined?) behaviour of destroy is a bug (a regression).On Sunday, 15 January 2017 at 15:56:30 UTC, Dsby wrote:the "writeln("I'm destroyed");" not run the ~this in the Unique destroy function. it run in the app exit , THe GC distroy all memony. it example can show : import std.stdio; import std.typecons; struct Foo { ~this() { writeln("I'm destroyed"); } } void fun(){ Unique!Foo foo = new Foo; writeln("exit the fun."); } void main() { fun(); writeln("exit the Main."); } It is the printf: ~/tmp rdmd ./type.d 2017年01月16日 星期一 09时50分00秒 exit the fun. exit the Main. I'm destroyed ~/tmp if you use the struct in Unique, the struct's Destory function is not run in the Unique destroy, it is also run in the GC collet. I think it is not the Unique should be.and : In https://github.com/dlang/phobos/blob/master/std/typecons.d#L147 ~this() { debug(Unique) writeln("Unique destructor of ", (_p is null)? null: _p); if (_p !is null) destroy(_p); _p = null; } if the 'T' is a struct, it will not exec the Destory function. Is it a bug?What do you mean? This works for me: --- import std.stdio, std.typecons; struct Foo { ~this() { writeln("I'm destroyed"); } } void main() { Unique!Foo foo = new Foo; } // Prints "I'm destroyed" ---
Jan 16 2017
On Friday, 13 January 2017 at 16:50:37 UTC, Dsby wrote:I write the ref count pointer and the scoped point in D. it just Like cpp's shared_ptr ， waek_ptr and unique_ptr . Now, it is Developing. I will write more test before the frist release. And the docs is null. It on github: https://github.com/huntlabs/SmartRefVery nice. Do you have a dub package for this?
May 29 2018
On Friday, 13 January 2017 at 16:50:37 UTC, Dsby wrote:I will write more test before the frist release. And the docs is null. It on github: https://github.com/huntlabs/SmartRefI hope you know https://code.dlang.org/packages/automem.
Jun 08 2018