Issue #10095 has been updated by Jihwan Song.


I should admit that I never liked object to which a block method is called being passed as block parameter.

Even for tap, for example, 
(1..10).tap{ |x| logger.debug x }

looks a bit < u guess >. I'd like to say 

(1..10).tap{ logger.debug self }

This is totally different with other cases where  block parameters are used:

members.each { |member| member.shake_hands }

Here, member is not same object as members.

However, in case of tap or this new feature we are discussing, or other cases where I had to pass self as block parameter, I always felt something is not right.



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Feature #10095: Object#as
https://bugs.ruby-lang.org/issues/10095#change-49033

* Author: Akira Matsuda
* Status: Open
* Priority: Normal
* Assignee: 
* Category: core
* Target version: current: 2.2.0
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We've had so many times of feature requests for a method similar to Object#tap that doesn't return self but returns the given block's execution result (e.g. #7388, #6684, #6721 ).

I'm talking about something like this in Ruby of course:
Object.class_eval { def as() yield(self) end }

IIRC Matz is not against introducing this feature but he didn't like any of the names proposed in the past, such as embed, do, identity, ergo, reference, yield_self, itself, apply, map, tap!, etc.

So, let us propose a new name, Object#as today.
It's named from the aspect of the feature that it gives the receiver a new name "as" a block local variable.
For instance, the code reads so natural and intuitive like this:

(1 + 2 + 3 + 4).as {|x| x ** 2}
=> 100

Array.new.as {|a| a << 1; a << 2}
=> [1, 2]

---Files--------------------------------
itself-block.patch (1.35 KB)


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