Here is an alternative to get the idea rolling.

def manage_ducks(ducks)
  if ducks.nil? || !ducks.won_stanley_cup?
    ducks = fetch_some_champions
  end
  ducks.beat_random_opponent
end

it doesn’t appear that wrapping in tags works.

ducks = fetch_some_champions unless ducks and ducks.won_stanley_cup?
ducks.beat_random_opponent

The code is ugly indeed. I agree with Aplha Chen’s suggestion, its the same I have came up with. Pretty and still nice and readable.

Here it is:

def manage_ducks(ducks)
  ducks = ducks.fetch_some_champions unless ducks.nil? || ducks.won_stanley_cup?
  ducks.beat_random_opponent
end

def manage_ducks(ducks)
  ducks = fetch_some_champions if ducks.nil? || !ducks.won_stanley_cup?
  ducks.beat_random_opponent
end

Nando and Alpha Chen solutions were exactly what I had in mind. IMHO, Nando’s solutions is a bit better, using the “nil?” method, which is easier to understand. Just a minor correction on the logic:

def manage_ducks(ducks)
  ducks = ducks.fetch_some_champions if ducks.nil? || !ducks.won_stanley_cup?
  ducks.beat_random_opponent
end

One thing I noticed no one was doing is taking advantage of Ruby returning an object from assignment. The whole ducks.beat_random_opponent thing can do without the ducks.

# Verbose
def manage_ducks(ducks)
  unless ducks and ducks.won_stanley_cup?
    fetch_some_champions
  else
    ducks
  end.beat_random_opponent
end

# Superterse, if Perl-y
def manage_ducks(ducks)
  ((ducks && ducks.won_stanley_cup?) ? ducks : fetch_some_champions).beat_random_opponent
end

Also, you don’t have to ask “if ducks.nil?” when “if ducks” works just fine and is perfectly idiomatic Ruby.

Thanks everyone for commenting in this first edition of Rubyize this (seeing it was quite popular there will be some more).

My favorite solution is without a doubt the one by Nando (once you remove the logic mistake like Silvio has pointed out) and Casey. In this situation I prefer the if over unless because it feels more natural. (unless ducks and ducks.won_stanley_cup? can be a bit confusing when you read it).

I’d also like to talk about RSL suggestions which I find very interesting (the second one is a bit cryptic… but still pretty nice). Although the first solution looks awkward at first, I find it extremely readable and clean. I’ll try to include some of this stuff in my applications in the future.

RSL, however I don’t understand your last comment. “if ducks.nil?” is definitely not the same as “if ducks”. I guess you wanted to say “unless ducks”.

Sorry… my bad!
I posted it without reviewing just to be fast.. huahahuahuau.

Woops. You’re right. I did have that backwards. I guess I shouldn’t post comments [especially not ones containing _code_] before I’ve finished my morning coffee.

A little late, but this is an interesting approach:

def manage_ducks(ducks)
throw(nil) unless ducks.won_stanley_cup? rescue ducks = fetch_some_champions
ducks.beat_random_opponent
end

A little weird, but it works. If ducks is nil, the unless clause will throw an exception; if
won_stanley_cup? is false, it throws a nil exception.