From: bughit.github@...
Date: 2019-09-06T17:37:05+00:00
Subject: [ruby-core:94808] [Ruby master Bug#12984] `rescue *[]` should be equivalent to `rescue` as `method_call(*[])` is equivalent to `method_call`

Issue #12984 has been updated by bughit (bug hit).


> The explicit syntax for rescue nothing is rescue *[] :)

Splat is not part of the rescue syntax, it composes with it, the same way it composes with other constructs that take a comma separated list (invocations, not sure if there are others).

Here's an excerpt from "The ruby programming language"

----------------------------------------------------------
Here���s how we would write a rescue clause to handle exceptions of either
of these types and assign the exception object to the variable error:

rescue ArgumentError, TypeError => error

Here, finally, we see the syntax of the rescue clause at its most general. The rescue
keyword is followed by zero or more comma-separated expressions, each of which must
evaluate to a class object that represents the Expression class or a subclass. These
expressions are optionally followed by => and a variable name.
------------------------------------------------------

It documents the specific synax of rescue but does not even mention the splat, which does not have any special meaning in this context and its general meaning is `*[] == a void list`, so `rescue *[] == rescue`

----------------------------------------
Bug #12984: `rescue *[]` should be equivalent to `rescue` as `method_call(*[])` is equivalent to `method_call`
https://bugs.ruby-lang.org/issues/12984#change-81429

* Author: bughit (bug hit)
* Status: Assigned
* Priority: Normal
* Assignee: matz (Yukihiro Matsumoto)
* Target version: 
* ruby -v: ruby 2.3.3p222 (2016-11-21 revision 56859) [x86_64-linux]
* Backport: 2.1: UNKNOWN, 2.2: UNKNOWN, 2.3: UNKNOWN
----------------------------------------
Splatting an empty array to a construct that takes a list is supposed to be equivalent to specifying no list

```ruby
def foo
end

foo *[] #works
```

So `rescue *[]` should be equivalent to `rescue`

```ruby
begin
  raise 'error' #Uncaught exception
rescue *[]
  puts 'caught'
end
```




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