Re: A better way?

Il giorno Wed, 8 Feb 2012 06:00:09 +0900
Dave Castellano <[e-mail]> ha scritto:

> Hi,
> 
> As I am learning to program, I am finding things I think can probably be
> done in a better way.  The following code seems like something
> programmers must run into all the time and I am wondering if there is a
> better way to write the code in this situation.  I'm having fun and
> trying to get better at this....
> 
>          if random_insert == 0
>             correct_answer_shuffled = "A"
>           elsif random_insert == 1
>             correct_answer_shuffled = "B"
>           elsif random_insert == 2
>             correct_answer_shuffled = "C"
>           elsif random_insert == 3
>             correct_answer_shuffled = "D"
>           elsif random_insert == 4
>             correct_answer_shuffled = "E"
>           end
> 
> Is there a better way??
> 
> Thanks...
> 
> Dave
> 

You can create a hash having the possible values of random_insert as keys and
the corresponding values you want to assign to correct_answer_shuffled as
values:

possible_answers = {0 => "A", 1 => "B", 2 => "C", 3 => "D", 4 => "E"}
correct_answer_shuffled = possible_answers[random_insert]

Given that the values of random_insert are positive integers, you can also
use an array instead of a hash:

possible_answers = ["A","B", "C", "D", "E"]
correct_answer_shuffled = possible_answers[random_insert]

You could also use a case expression, which gives code more similar to what
you wrote:

correct_answer_shuffled = case random_insert
  when 0 then "A"
  when 1 then "B"
  when 2 then "C"
  when 3 then "D"
  when 4 then "E"
end

This is best used when you have to perform different operations depending on
the value of random_insert, rather than using a different, fixed value. In
this case, an array or hash are better solution.

I hope this helps

Stefano