A 3.3 feature that was merged in the last moment

Author: zverok

2.4.md

@@ -16,9 +16,9 @@ description: Ruby 2.4 full and annotated changelog
  -->
 
 * **Released at:** Dec 25, 2016 (<a class="github" href="https://github.com/ruby/ruby/blob/trunk/doc/NEWS-2.4.0">NEWS</a> file)
-* **Status (as of Dec 21, 2023):** EOL, latest is 2.4.10
+* **Status (as of Dec 25, 2023):** EOL, latest is 2.4.10
 * **This document first published:** Oct 14, 2019
-* **Last change to this document:** Dec 21, 2023
+* **Last change to this document:** Dec 25, 2023
 
 ## Highlights[](#highlights)
 

2.7.md

@@ -8,9 +8,9 @@ description: Ruby 2.7 full and annotated changelog
 # Ruby 2.7
 
 * **Released at:** Dec 25, 2019 (<a class="github" href="https://github.com/ruby/ruby/blob/ruby_2_7/NEWS">NEWS</a> file)
-* **Status (as of Dec 21, 2023):** 2.7.8 is EOL
+* **Status (as of Dec 25, 2023):** 2.7.8 is EOL
 * **This document first published:** Dec 27, 2019
-* **Last change to this document:** Dec 21, 2023
+* **Last change to this document:** Dec 25, 2023
 
 <!-- TODO: all links to docs should be replaced with /2.7.0/ suffix instead of /master/ when 2.7.0 would be published -->
 

3.0.md

@@ -8,9 +8,9 @@ description: Ruby 3.0 full and annotated changelog
 # Ruby 3.0
 
 * **Released at:** Dec 25, 2020 (<a class="github" href="https://github.com/ruby/ruby/blob/ruby_3_0/NEWS.md">NEWS.md</a> file)
-* **Status (as of Dec 23, 2023):** 3.0.6 is security maintenance (will EOL soon!)
+* **Status (as of Dec 25, 2023):** 3.0.6 is security maintenance (will EOL soon!)
 * **This document first published:** Dec 25, 2020
-* **Last change to this document:** Dec 23, 2023
+* **Last change to this document:** Dec 25, 2023
 
 ## Highlights[](#highlights)
 

3.2.md

@@ -8,9 +8,9 @@ description: Ruby 3.2 full and annotated changelog
 # Ruby 3.2
 
 * **Released at:** Dec 25, 2022 (<a class="github" href="https://github.com/ruby/ruby/blob/ruby_3_2/NEWS.md">NEWS.md</a> file)
-* **Status (as of Dec 24, 2023):** 3.2.2 is current _stable_
+* **Status (as of Dec 25, 2023):** 3.2.2 is current _stable_
 * **This document first published:** Feb 4, 2022
-* **Last change to this document:** Dec 24, 2023
+* **Last change to this document:** Dec 25, 2023
 
 <!--
 * **Reason:**

3.3.md

@@ -65,6 +65,48 @@ In Ruby 3.3, it will just warn to prepare for a change.
   ```
 * **Notes:** The new feature isn't expected to conflict with RSpec's [`it`](https://rspec.info/documentation/3.12/rspec-core/RSpec/Core/ExampleGroup.html#it-class_method), as calling that without any block attached, or at least a description for the future example, is useless.
 
+### Anonymous parameters forwarding inside blocks are disallowed[](#anonymous-parameters-forwarding-inside-blocks-are-disallowed)
+
+Now anonymous parameters forwarding inside a block raise error.
+
+* **Reason:** Blocks didn't support anonymous parameters _forwarding_, yet they supported anonymous parameters _declaration_, and it was a confusing situation (when something that looked like block forwarding its parameters, actually forwarded parameters of the method containing the block).
+* **Discussion:** <a class="tracker feature" href="https://bugs.ruby-lang.org/issues/19370">Feature #19370</a>
+* **Code:**
+  ```ruby
+  def m(*)
+    # ..some other code using anonymous params...
+
+    [1, 2, 3].each { |*| p(*) }
+  end
+  m('test')
+
+  # Ruby 3.2:
+  #  The block above looks like it would forward its arguments to p
+  #  (so it would print 1, 2, 3); but actually anonymous params of the _method_
+  #  are forwarded, so it actually prints:
+  #   "test"
+  #   "test"
+  #   "test"
+
+  # Ruby 3.3:
+  #   anonymous rest parameter is also used within block (SyntaxError)
+  # (raised during parsing the file)
+
+  # No error is raised if there's no perceived conflict of anonymous
+  # params:
+  def m(*)
+    # ..some other code using anonymous params...
+
+    [1, 2, 3].each { |i| p(*) } # no question what `*` refers to
+  end
+  m('test')
+  # Ruby 3.3:
+  #   "test"
+  #   "test"
+  #   "test"
+  ```
+* **Notes:** There is a [question](https://bugs.ruby-lang.org/issues/19370#note-9) whether disallowing block parameters forwarding is the best way to solve the confusion; alternative solution would be just to support forwarding inside the block properly. I hope the discussion to continue during 3.4 development.
+
 ## Core classes and modules[](#core-classes-and-modules)
 
 ### `Kernel#lambda` raises when passed `Proc` instance[](#kernellambda-raises-when-passed-proc-instance)

_data/book.yml

@@ -119,6 +119,8 @@ chapters:
     - title: Standalone <code>it</code> in blocks will become anonymous argument in
         Ruby 3.4
       path: "/3.3.html#standalone-it-in-blocks-will-become-anonymous-argument-in-ruby-34"
+    - title: Anonymous parameters forwarding inside blocks are disallowed
+      path: "/3.3.html#anonymous-parameters-forwarding-inside-blocks-are-disallowed"
   - title: Core classes and modules
     path: "/3.3.html#core-classes-and-modules"
     children:

_src/3.3.md

@@ -65,6 +65,48 @@ In Ruby 3.3, it will just warn to prepare for a change.
   ```
 * **Notes:** The new feature isn't expected to conflict with RSpec's [`it`](https://rspec.info/documentation/3.12/rspec-core/RSpec/Core/ExampleGroup.html#it-class_method), as calling that without any block attached, or at least a description for the future example, is useless.
 
+### Anonymous parameters forwarding inside blocks are disallowed
+
+Now anonymous parameters forwarding inside a block raise error.
+
+* **Reason:** Blocks didn't support anonymous parameters _forwarding_, yet they supported anonymous parameters _declaration_, and it was a confusing situation (when something that looked like block forwarding its parameters, actually forwarded parameters of the method containing the block).
+* **Discussion:** [Feature #19370](https://bugs.ruby-lang.org/issues/19370)
+* **Code:**
+  ```ruby
+  def m(*)
+    # ..some other code using anonymous params...
+
+    [1, 2, 3].each { |*| p(*) }
+  end
+  m('test')
+
+  # Ruby 3.2:
+  #  The block above looks like it would forward its arguments to p
+  #  (so it would print 1, 2, 3); but actually anonymous params of the _method_
+  #  are forwarded, so it actually prints:
+  #   "test"
+  #   "test"
+  #   "test"
+
+  # Ruby 3.3:
+  #   anonymous rest parameter is also used within block (SyntaxError)
+  # (raised during parsing the file)
+
+  # No error is raised if there's no perceived conflict of anonymous
+  # params:
+  def m(*)
+    # ..some other code using anonymous params...
+
+    [1, 2, 3].each { |i| p(*) } # no question what `*` refers to
+  end
+  m('test')
+  # Ruby 3.3:
+  #   "test"
+  #   "test"
+  #   "test"
+  ```
+* **Notes:** There is a [question](https://bugs.ruby-lang.org/issues/19370#note-9) whether disallowing block parameters forwarding is the best way to solve the confusion; alternative solution would be just to support forwarding inside the block properly. I hope the discussion to continue during 3.4 development.
+
 ## Core classes and modules
 
 ### `Kernel#lambda` raises when passed `Proc` instance

_src/evolution.md

@@ -355,14 +355,15 @@ This section lists changes in how methods are defined and invoked, as well as ne
     File.open(filename, &)
   end
   ```
-* [3.2](3.2.md#anonymous-arguments-passing-improvements) Anonymous keyword and positional arguments ([Methods: Array/Hash Argument](https://docs.ruby-lang.org/en/3.2/syntax/methods_rdoc.html#label-Array-2FHash+Argument)):
+* [3.2](3.2.md#anonymous-arguments-passing-improvements) Anonymous keyword and positional arguments forwarding ([Methods: Array/Hash Argument](https://docs.ruby-lang.org/en/3.2/syntax/methods_rdoc.html#label-Array-2FHash+Argument)):
   ```ruby
   # Only accepts positional arguments and passes them further
   def log(level, *) = logger.log(level, *)
 
   # Only accepts anonymous keyword args and passes them further
   def get(url, **) = send_request(:get, url, **)
   ```
+  * [3.3](3.3.md#anonymous-parameters-forwarding-inside-blocks-are-disallowed) Anonymous parameters forwarding inside blocks are disallowed, when the block also has anonymous parameters.
 
 <!--
 * [3.1](3.1.md#inside-endless-method-definitions-method-calls-without-parenthesis-are-allowed) Inside "endless" method definitions, method calls without parenthesis are allowed (— ([doc/syntax/methods.rdoc](https://docs.ruby-lang.org/en/3.1/syntax/methods_rdoc.html) doesn't mention new or old behavior.))

evolution.md

@@ -355,14 +355,15 @@ This section lists changes in how methods are defined and invoked, as well as ne
     File.open(filename, &)
   end
   ```
-* <span class="ruby-version">[3.2](3.2.md#anonymous-arguments-passing-improvements)</span> Anonymous keyword and positional arguments (<a class="ruby-doc" href="https://docs.ruby-lang.org/en/3.2/syntax/methods_rdoc.html#label-Array-2FHash+Argument">Methods: Array/Hash Argument</a>):
+* <span class="ruby-version">[3.2](3.2.md#anonymous-arguments-passing-improvements)</span> Anonymous keyword and positional arguments forwarding (<a class="ruby-doc" href="https://docs.ruby-lang.org/en/3.2/syntax/methods_rdoc.html#label-Array-2FHash+Argument">Methods: Array/Hash Argument</a>):
   ```ruby
   # Only accepts positional arguments and passes them further
   def log(level, *) = logger.log(level, *)
 
   # Only accepts anonymous keyword args and passes them further
   def get(url, **) = send_request(:get, url, **)
   ```
+  * <span class="ruby-version">[3.3](3.3.md#anonymous-parameters-forwarding-inside-blocks-are-disallowed)</span> Anonymous parameters forwarding inside blocks are disallowed, when the block also has anonymous parameters.
 
 <!--
 * <span class="ruby-version">[3.1](3.1.md#inside-endless-method-definitions-method-calls-without-parenthesis-are-allowed)</span> Inside "endless" method definitions, method calls without parenthesis are allowed (— (<a class="ruby-doc" href="https://docs.ruby-lang.org/en/3.1/syntax/methods_rdoc.html"><code>doc/syntax/methods.rdoc</code></a> doesn't mention new or old behavior.))