Accessing the current array inside a ruby method

Question

Is there a way to use the array being acted upon inside of a method, like how in javascript you can send a copy of that array to the callback?

so something like:

array.something.somethingelse.anotherthing do |element|

    #i want to be able to use array.something.somethingelse here without 
    #having to call something and somethingelse on the original array again

end

Just extract it in a variable, then call `anotherthing` on it. Or that `anotherthing` could indeed send it to the block (if it's a method you write) — Sergio Tulentsev, Dec 10 '17 at 22:38
@SergioTulentsev In this example 'anotherthing' is not intended to be a method I write, and I am curious if there is a way to access the modified array inside of the method block, like the way it can be done in javascript — jjames, Dec 10 '17 at 22:48
What is `anotherthing`? Do you really need both `element` *and* `array.something.somethingelse` in that block? Do you have an actual example? — Stefan Pochmann, Dec 10 '17 at 23:40

score 3 · Answer 1 · answered Dec 11 '17 at 01:36

It's highly irregular, but you can always do this:

array.something.somethingelse.tap do |se|
  se.anotherthing do |element|
  end    
end

Normally you'd create an intermediate variable:

se = array.something.somethingelse

se.anotherthing do |element|
end

There's no real advantage to the tap approach, it doesn't make the code more readable.

In all honesty the best approach is to delegate this to a function like:

do_another_thing(array.something.somethingelse)

And then there you have a free variable by virtue of it being the argument:

def do_another_thing(se)
  se.anotherthing do |element|
  end
end

Accessing the current array inside a ruby method

1 Answers1