[#103135] [Ruby master Feature#17768] Proposal: Downward assignments — mame@...

Issue #17768 has been reported by mame (Yusuke Endoh).

10 messages 2021/04/01

[#103162] [Ruby master Feature#17773] Alias `Numeric#zero?` and `Float#zero?` as `Numeric#empty?` and `Float#empty?` — sawadatsuyoshi@...

Issue #17773 has been reported by sawa (Tsuyoshi Sawada).

9 messages 2021/04/02

[#103241] [Ruby master Bug#17777] 2.6.7 fails to build on macOS: implicit declaration of function 'rb_native_mutex_destroy' is invalid in C99 — eregontp@...

Issue #17777 has been reported by Eregon (Benoit Daloze).

17 messages 2021/04/05

[#103280] [Ruby master Bug#17781] Resolv::DNS RequestID table allocations are never freed, causing DNS lookups to eventually hang — supermathie@...

Issue #17781 has been reported by supermathie (Michael Brown).

9 messages 2021/04/07

[#103305] [Ruby master Feature#17785] Allow named parameters to be keywords — marcandre-ruby-core@...

Issue #17785 has been reported by marcandre (Marc-Andre Lafortune).

21 messages 2021/04/08

[#103310] [Ruby master Feature#17786] Proposal: new "ends" keyword — jzakiya@...

Issue #17786 has been reported by jzakiya (Jabari Zakiya).

13 messages 2021/04/08

[#103317] [Ruby master Bug#17787] Four AIX build issues with xlc compiler and ruby-3.0.1 — lamont@...

Issue #17787 has been reported by lamont (Lamont Granquist).

9 messages 2021/04/08

[#103342] [Ruby master Feature#17790] Have a way to clear a String without resetting its capacity — jean.boussier@...

Issue #17790 has been reported by byroot (Jean Boussier).

14 messages 2021/04/09

[#103386] [Ruby master Bug#17793] `shorten-64-to-32` error for 32-bit Android due to `struct stat` definition — xtkoba+ruby@...

Issue #17793 has been reported by xtkoba (Tee KOBAYASHI).

8 messages 2021/04/11

[#103400] [Ruby master Feature#17795] `before_fork` and `after_fork` callback API — jean.boussier@...

Issue #17795 has been reported by byroot (Jean Boussier).

42 messages 2021/04/12

[#103434] [Ruby master Bug#17799] Seg fault in rb_class_clear_method_cache — stanhu@...

Issue #17799 has been reported by stanhu (Stan Hu).

14 messages 2021/04/13

[#103481] [Ruby master Feature#17808] Feature Request: JS like splat of Object properties as named method parameters — brad.krane@...

Issue #17808 has been reported by Lithium (Brad Krane).

8 messages 2021/04/16

[#103556] [Ruby master Bug#17820] `Errno::EINVAL` from `Process.kill` with available signal on Windows — alex.wayfer@...

Issue #17820 has been reported by AlexWayfer (Alexander Popov).

9 messages 2021/04/22

[#103591] [Ruby master Bug#17827] Monitor is not fiber safe — samuel@...

Issue #17827 has been reported by ioquatix (Samuel Williams).

11 messages 2021/04/25

[#103593] [Ruby master Misc#17828] Deprecate use of master and slave — yyoshida.at.work@...

Issue #17828 has been reported by yyoshida.at.work@gmail.com (Yasuhiro Yoshida).

10 messages 2021/04/26

[#103596] [Ruby master Feature#17830] Add Integer#previous and Integer#prev — rafasoaresms@...

Issue #17830 has been reported by rafasoares (Rafael Soares).

9 messages 2021/04/26

[#103631] [Ruby master Feature#17837] Add support for Regexp timeouts — sam.saffron@...

Issue #17837 has been reported by sam.saffron (Sam Saffron).

45 messages 2021/04/27

[ruby-core:103546] [Ruby master Feature#17790] Have a way to clear a String without resetting its capacity

From: dsisnero@...
Date: 2021-04-21 23:27:52 UTC
List: ruby-core #103546
Issue #17790 has been updated by dsisnero (Dominic Sisneros).


That was what I was hoping the addition of memoryview would help with but the only way to interact with the memoryview in ruby is with Fiddle
If we had a ByteArray class that implemented memoryview 

buffer = ByteArray.new('this is a string'.bytes)  
mv = Fiddle::MemoryView.new(buffer)
mv.byte_size # 16
first8 = mv[0:8]   # once Fiddle::MemoryView allows you to slice
socket.write(first8)   # once socket.write allows you to write memoryview objects without changing into string. 

What memoryview is supposed to do is allow the reading and writing with zero copy because it knows the offsets, strides, etc of the underlying obj in the buffer

So, I think we should instead finish the parts of memoryview that are missing:

1) IO support for memoryview (read into a memoryview object and write from a memoryview object without converting to strings)
2) Add classes that implement the memoryview protocol  
3) change String.bytes to return a new ByteArray class that implements the memoryview protocol
4) add a ruby extension that allows you to use memory view objects in ruby (not just Fiddle) 
   mv = MemoryView.new(obj)
   mv[offset:offset_size]   #slicing memory views
   mv.cast(format, shape)  - change format or shape of memoryview but keep data
  mv.format
  mv.strides
  mv.shape
   





----------------------------------------
Feature #17790: Have a way to clear a String without resetting its capacity
https://bugs.ruby-lang.org/issues/17790#change-91647

* Author: byroot (Jean Boussier)
* Status: Open
* Priority: Normal
----------------------------------------
In some tight loop it can be useful to re-use a buffer string. For instance:

```ruby
buffer = String.new(encoding: Encoding::BINARY, capacity: 1024)

10.times do
  build_next_packet(buffer)
  udp_socket.send(buffer)
  buffer.clear
end
```

Currently `Array#clear` preserve the Array capacity, but `String#clear` doesn't:

```ruby
>> puts ObjectSpace.dump(Array.new(20).clear)
{"address":"0x7fd3260a1558", "type":"ARRAY", "class":"0x7fd3230972e0", "length":0, "memsize":200, "flags":{"wb_protected":true}}
>> puts ObjectSpace.dump(String.new(encoding: Encoding::BINARY, capacity: 1024).clear)
{"address":"0x7fd322a8a320", "type":"STRING", "class":"0x7fd3230b75b8", "embedded":true, "bytesize":0, "value":"", "memsize":40, "flags":{"wb_protected":true}}
```

It would be useful if `String#clear` wouldn't free allocated memory, but if it's a backward compatibility concern to change it, then maybe another method could make sense?




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