March 2024 - ruby-core - ml.ruby-lang.org

[ruby-core:114403] [Ruby master Feature#19840] [Proposal] Expand Find pattern to Multiple Find
by FlickGradley (Nick Bradley) 15 May '24

15 May '24

Issue #19840 has been reported by FlickGradley (Nick Bradley). ---------------------------------------- Feature #19840: [Proposal] Expand Find pattern to Multiple Find https://bugs.ruby-lang.org/issues/19840 * Author: FlickGradley (Nick Bradley) * Status: Open * Priority: Normal ---------------------------------------- Hello! I love Ruby's pattern matching features. I would like to propose an expansion of the Find pattern which allows the selection of multiple matching elements of an array. I often find myself dealing with data like this: ``` ruby { results: [{ id: 1, name: "foo" }, { id: 2, name: "bar" }, ... ] } ``` My problem is that I need to retrieve all the `id` values from the nested array of hashes, and I don't know how many there will be in advance. It seems that the Find pattern could be expanded from allowing `pattern` (matching a single element) to `*pattern`. Examples: ``` ruby # Base case case { results: [{ id: 1, name: "foo" }, { id: 2, name: "bar" }] } in results: [*{ id: ids }] "matched: #{ids}" else "not matched" end #=> matched: [1, 2] # With * at the end (rest of args) - same result case { results: [{ id: 1, name: "foo" }, { id: 2, name: "bar" }] } in results: [*{ id: ids }, *] "matched: #{ids}" else "not matched" end #=> matched: [1, 2] # When one element doesn't match and there is no *rest case { results: [{ name: "foo" }, { id: 2, name: "bar" }] } in results: [*{ id: ids }] "matched: #{ids}" else "not matched" end #=> not matched ``` Similarly, `*Constant` could work to pull out types with an As pattern: ``` ruby case [1, 2, 3, "string"] in *Integer => nums, * "matched: #{nums}" else "not matched" end #=> matched: [1, 2, 3] ``` Other patterns would work in the same way. Essentially, this expands the concept of `*` in pattern matching to mean "a variable number of `things matching subpattern`". Today, the only pattern supported by `*` is a variable binding - but it could be any of the other subpatterns as well. This proposal does imply that this would work: ``` ruby a = 2 [1, 2, 2, 3] in [*, *^a, *] #=> true ``` To me, the `*` represents the variable number of matches, so the syntax makes intuitive sense. But others may have different opinions about `*^` being adjacent. It may also imply this would work, though we could restrict the number of non-variable patterns (in other words, patterns that have the possibility of not matching) to 1 per Array so that this isn't possible.. I'm not sure something like this would be useful or clear. ``` ruby a = 2 [1, 2, "hello", "ruby"] in [*Integer, *String] #=> true ``` This feature feels like the missing piece of the Find pattern to me - I often want to "Find Multiple". If others agree, I would be happy to contribute by working on this feature and creating a pull request. -- https://bugs.ruby-lang.org/

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[ruby-core:116940] [Ruby master Feature#20300] Hash: set value and get pre-existing value in one call
by AMomchilov (Alexander Momchilov) 11 May '24

11 May '24

Issue #20300 has been reported by AMomchilov (Alexander Momchilov). ---------------------------------------- Feature #20300: Hash: set value and get pre-existing value in one call https://bugs.ruby-lang.org/issues/20300 * Author: AMomchilov (Alexander Momchilov) * Status: Open ---------------------------------------- When using a Hash, sometimes you want to set a new value, *and* see what was already there. Today, you **have** to do this in two steps: ```ruby h = { k: "old value" } # 1. Do a look-up for `:k`. old_value = h[:k] # 2. Do another look-up for `:k`, even though we just did that! h[:k] = "new value" use(old_value) ``` This requires two separate `Hash` look-ups for `:k`. This is fine for symbols, but is expensive if computing `#hash` or `#eql?` is expensive for the key. It's impossible to work around this today from pure Ruby code. I propose adding `Hash#update_value`, which has semantics are similar to this Ruby snippet: ```ruby class Hash def update_value(key, new_value) old_value = self[key] self[key] = new_value old_value end end ``` ... except it'll be implemented in C, with modifications to `tbl_update` that achieves this with a hash-lookup. Here's a PR with a PoC implementation: https://github.com/ruby/ruby/pull/10092 -- https://bugs.ruby-lang.org/

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[ruby-core:116802] [Ruby master Misc#20272] Ambiguity around Ractor message sending FIFO semantics
by forthoney (Seong-Heon Jung) 26 Apr '24

26 Apr '24

Issue #20272 has been reported by forthoney (Seong-Heon Jung). ---------------------------------------- Misc #20272: Ambiguity around Ractor message sending FIFO semantics https://bugs.ruby-lang.org/issues/20272 * Author: forthoney (Seong-Heon Jung) * Status: Open * Priority: Normal ---------------------------------------- The docs should explicitly state the semantics/properties of Ractor message, especially when it comes to FIFO. For example, assume I have two Ractors, Ractor A and Ractor B. Ractor A sends two messages `"hello"` and `"world"` in this order to Ractor B. If I call `Ractor.receive` on Ractor B, am I guaranteed to see `"hello"` and then `"world"` or is it possible the messages are delivered out of order? -- https://bugs.ruby-lang.org/

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[ruby-core:116218] [Ruby master Bug#20186] Ripper does not generate AST for some keywords in Ruby 3.3
by kzkn (Kazuki Nishikawa) 24 Apr '24

24 Apr '24

Issue #20186 has been reported by kzkn (Kazuki Nishikawa). ---------------------------------------- Bug #20186: Ripper does not generate AST for some keywords in Ruby 3.3 https://bugs.ruby-lang.org/issues/20186 * Author: kzkn (Kazuki Nishikawa) * Status: Open * Priority: Normal * ruby -v: 3.3.0 * Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN ---------------------------------------- Ripper does not generate AST for the below keyword: - break - next - redo - retry - yield Ruby 3.2 ``` $ ruby -v ruby 3.2.2 (2023-03-30 revision e51014f9c0) [x86_64-linux] $ ruby -rripper -e "p Ripper.sexp('break')" [:program, [[:break, []]]] $ ruby -rripper -e "p Ripper.sexp('next')" [:program, [[:next, []]]] $ ruby -rripper -e "p Ripper.sexp('redo')" [:program, [[:redo]]] $ ruby -rripper -e "p Ripper.sexp('retry')" [:program, [[:retry]]] $ ruby -rripper -e "p Ripper.sexp('yield')" [:program, [[:yield0]]] ``` Ruby 3.3 ``` $ ruby -v ruby 3.3.0 (2023-12-25 revision 5124f9ac75) [x86_64-linux] $ ruby -rripper -e "p Ripper.sexp('break')" nil $ ruby -rripper -e "p Ripper.sexp('next')" nil $ ruby -rripper -e "p Ripper.sexp('redo')" nil $ ruby -rripper -e "p Ripper.sexp('retry')" nil $ ruby -rripper -e "p Ripper.sexp('yield')" nil ``` -- https://bugs.ruby-lang.org/

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[ruby-core:116687] [Ruby master Bug#20262] Regex mismatch between Ruby 3.2.2 and 3.3.0
by weilandia (Nick Weiland) 24 Apr '24

24 Apr '24

Issue #20262 has been reported by weilandia (Nick Weiland). ---------------------------------------- Bug #20262: Regex mismatch between Ruby 3.2.2 and 3.3.0 https://bugs.ruby-lang.org/issues/20262 * Author: weilandia (Nick Weiland) * Status: Open * Priority: Normal * ruby -v: 3.3.0 * Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN ---------------------------------------- This might be a duplicate of https://bugs.ruby-lang.org/issues/20098, but I cannot make it match with the backref so maybe not. Below example matches in 3.2.2 but not in 3.3.0 ``` ruby str = "------------abcdefg------------#3895912" re = /()\1\b\w*[a-zA-Z-]*\d+[\w-]{3,}\w+\b/ re.match?(str) ``` -- https://bugs.ruby-lang.org/

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[ruby-core:116456] [Ruby master Feature#20215] Introduce `IO#readable?`
by ioquatix (Samuel Williams) 21 Apr '24

21 Apr '24

Issue #20215 has been reported by ioquatix (Samuel Williams). ---------------------------------------- Feature #20215: Introduce `IO#readable?` https://bugs.ruby-lang.org/issues/20215 * Author: ioquatix (Samuel Williams) * Status: Open * Priority: Normal ---------------------------------------- There are some cases where, as an optimisation, it's useful to know whether more data is potentially available. We already have `IO#eof?` but the problem with using `IO#eof?` is that it can block indefinitely for sockets. Therefore, code which uses `IO#eof?` to determine if there is potentially more data, may hang. ```ruby def make_request(path = "/") client = connect_remote_host # HTTP/1.0 request: client.write("GET #{path} HTTP/1.0\r\n\r\n") # Read response client.gets("\r\n") # => "HTTP/1.0 200 OK\r\n" # Assuming connection close, there are two things the server can do: # 1. peer.close # 2. peer.write(...); peer.close if client.eof? # <--- Can hang here! puts "Connection closed" # Avoid yielding as we know there definitely won't be any data. else puts "Connection open, data may be available..." # There might be data available, so yield. yield(client) end ensure client&.close end make_request do |client| puts client.read # <--- Prefer to wait here. end ``` The proposed `IO#readable?` is similar to `IO#eof?` but rather than blocking, would simply return false. The expectation is the user will subsequently call `read` which may then wait. The proposed implementation would look something like this: ```ruby class IO def readable? !!self.closed? end end class BasicSocket # Is it likely that the socket is still connected? # May return false positive, but won't return false negative. def readable? return false unless super # If we can wait for the socket to become readable, we know that the socket may still be open. result = self.recv_nonblock(1, MSG_PEEK, exception: false) # No data was available - newer Ruby can return nil instead of empty string: return false if result.nil? # Either there was some data available, or we can wait to see if there is data avaialble. return !result.empty? || result == :wait_readable rescue Errno::ECONNRESET # This might be thrown by recv_nonblock. return false end end ``` For `IO` itself, when there is buffered data, `readable?` would also return true immediately, similar to `eof?`. This is not shown in the above implementation as I'm not sure if there is any Ruby method which exposes "there is buffered data". -- https://bugs.ruby-lang.org/

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[ruby-core:117157] [Ruby master Misc#20336] DevMeeting-2024-04-17
by mame (Yusuke Endoh) 18 Apr '24

18 Apr '24

Issue #20336 has been reported by mame (Yusuke Endoh). ---------------------------------------- Misc #20336: DevMeeting-2024-04-17 https://bugs.ruby-lang.org/issues/20336 * Author: mame (Yusuke Endoh) * Status: Open ---------------------------------------- # The next dev meeting **Date: 2024/04/17 13:00-17:00** (JST) Log: *TBD* - Dev meeting *IS NOT* a decision-making place. All decisions should be done at the bug tracker. - Dev meeting is a place we can ask Matz, nobu, nurse and other developers directly. - Matz is a very busy person. Take this opportunity to ask him. If you can not attend, other attendees can ask instead of you (if attendees can understand your issue). - We will write a record of the discussion in the file or to each ticket in English. - All activities are best-effort (keep in mind that most of us are volunteer developers). - The date, time and place of the meeting are scheduled according to when/where we can reserve Matz's time. - *DO NOT* discuss then on this ticket, please. # Call for agenda items If you have a ticket that you want matz and committers to discuss, please post it into this ticket in the following format: ``` * [Ticket ref] Ticket title (your name) * Comment (A summary of the ticket, why you put this ticket here, what point should be discussed, etc.) ``` Example: ``` * [Feature #14609] `Kernel#p` without args shows the receiver (ko1) * I feel this feature is very useful and some people say :+1: so let discuss this feature. ``` - It is recommended to add a comment by 2024/04/14. We hold a preparatory meeting to create an agenda a few days before the dev-meeting. - The format is strict. We'll use [this script to automatically create an markdown-style agenda](https://gist.github.com/mame/b0390509ce1491b43610b9ebb665eb86). We may ignore a comment that does not follow the format. - Your comment is mandatory. We cannot read all discussion of the ticket in a limited time. We appreciate it if you could write a short summary and update from a previous discussion. -- https://bugs.ruby-lang.org/

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[ruby-core:117341] [Ruby master Feature#20396] ObjectSpace.dump_all(string_value: false): skip dumping the String contents
by byroot (Jean Boussier) 18 Apr '24

18 Apr '24

Issue #20396 has been reported by byroot (Jean Boussier). ---------------------------------------- Feature #20396: ObjectSpace.dump_all(string_value: false): skip dumping the String contents https://bugs.ruby-lang.org/issues/20396 * Author: byroot (Jean Boussier) * Status: Open ---------------------------------------- `ObjectSpace.dump_all` is a very useful method to debug memory leaks and such, hence is frequently needed in production. But since all the 7bit strings content is included in the dump, it incur the risk of leaking personal data, or secrets. Also, in many case the strings content isn't that helpful and is just making the dump much bigger for no good reason. And only pure-ASCII strings are dumped this way, which means all the tools that process these dumps should already be compatible with a dump without any string content. ### Feature I propose to add another optional parameter to `dump_all`: `string_value: false`. When passed, no String content is ever dumped regardless of its coderange. Implementation: https://github.com/ruby/ruby/pull/10382 cc @zzak -- https://bugs.ruby-lang.org/

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[ruby-core:116892] [Ruby master Misc#20287] DevMeeting before or after RubyKaigi
by duerst 18 Apr '24

18 Apr '24

Issue #20287 has been reported by duerst (Martin Dürst). ---------------------------------------- Misc #20287: DevMeeting before or after RubyKaigi https://bugs.ruby-lang.org/issues/20287 * Author: duerst (Martin Dürst) * Status: Open * Priority: Normal ---------------------------------------- RubyKaigi itself runs from May 15-17 (Wed-Fri) in Naha. It would be nice to have a DevMeeting before or afterwards. We should try to plan ahead, so that people can make the right flight and hotel reservations early. I have never been to Okinawa before and don't know any facilities that would be available. -- https://bugs.ruby-lang.org/

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[ruby-core:117147] [Ruby master Feature#20335] `Thread.each_caller_location` should accept the same arguments as `caller` and `caller_locations`
by byroot (Jean Boussier) 17 Apr '24

17 Apr '24

Issue #20335 has been reported by byroot (Jean Boussier). ---------------------------------------- Feature #20335: `Thread.each_caller_location` should accept the same arguments as `caller` and `caller_locations` https://bugs.ruby-lang.org/issues/20335 * Author: byroot (Jean Boussier) * Status: Open ---------------------------------------- `Thread.each_caller_location` was added to Ruby 3.2 as part of [Feature #16663] and is a very useful API for emitting warnings with a proper source location and similar use cases. However in many of the cases where I used it, or seen it used, it was needed to skip the first, or a couple frames: Examples: Sorbet: https://github.com/Shopify/sorbet/blob/b27a14c247ace7cabdf0f348bfb11fdf0b7e… ```ruby def self.find_caller skiped_first = false Thread.each_caller_location do |loc| unless skiped_first skiped_first = true next end next if loc.path&.start_with?("<internal:") return loc if yield(loc) end nil end ``` @fxn's PR: https://github.com/ruby/ruby/blob/9c2e686719a5a4df5ea0b8a3b6a373ca6003c229/… ```ruby frames_to_skip = 2 location = nil Thread.each_caller_location do |cl| if frames_to_skip >= 1 frames_to_skip -= 1 next end # snipp... ``` ### Proposal I think it would be very useful if `Thread.each_caller_location` accepted the same arguments as `caller` and `caller_locations`: ```ruby #each_caller_location(start = 1, length = nil) #each_caller_location(range) ``` @jeremyevans0 what do you think? -- https://bugs.ruby-lang.org/

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