From: mail@...
Date: 2019-02-15T10:20:40+00:00
Subject: [ruby-core:91558] [Ruby trunk Feature#15574] Prohibit to pass a block on super() implicitly

Issue #15574 has been updated by sos4nt (Stefan Sch����ler).


I prefer the current behavior. Passing along a block is much more common than removing a block.

Let's say I have a class which yields `self` during initialization:

```ruby
class A
  def initialize(foo)
    # ...
    yield self if block_given?
  end
end
```

I can easily subclass the above and add an extra argument via:

```ruby
class B < A
  def initialize(foo, bar = nil)
    # ...
    super(foo)
  end
end
```

I don't even have to know whether `A` takes a block or not, Ruby takes care of it.

With the proposed change however, it becomes my responsibility. Almost every time I use `super(...)` I have to remember passing the block. The above code would become:

```ruby
class B < A
  def initialize(foo, bar = nil, &block)
    # ...
    super(foo, &block)
  end
end
```

Adding an explicit `&block` (and therefore creating a `Proc` object) for the sake of passing it along is something I'd like to avoid.

---

BTW, if you really have to remove all arguments including the block argument, it's merely:

```ruby
super(&nil)
```

That looks just fine to me.

----------------------------------------
Feature #15574: Prohibit to pass a block on super() implicitly
https://bugs.ruby-lang.org/issues/15574#change-76821

* Author: ko1 (Koichi Sasada)
* Status: Open
* Priority: Normal
* Assignee: matz (Yukihiro Matsumoto)
* Target version: 
----------------------------------------
As described in [Feature #15554], `super()` (not `super`) pass the given block.

```
class C
  def foo
    p block_given?
  end
end

class C1 < C
  def foo
    super   #=> true
    super() #=> true
  end
end

C1.new.foo{}
```

`super` (without parameters) passes all passed parameters so it is no surprise to pass given block. 

However, `super()` (with parameters. In this case, it passes 0 parameters) also pass given block implicitly.

I'm not sure who use this behavior, but I think it is simple to prohibit such implicit block passing.




-- 
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