Ruby Italian Style

Ruby is a great language because some tasks can be achieved in different ways.

The way you choose can be the most readable and beautiful.

Today I want to show you different ways to do a sum on values returned from different methods.

def negative
  25
end

def positive
  25
end

def neutral
 50
end

The result that we want is this:

  (negative + positive + neutral)
  # => 100

First way: collect all the values in an array and then inject + on it. (http://apidock.com/ruby/Enumerable/inject)

  %w(negative positive neutral).collect{ |m| send(m) }.inject(:+)
  # => 100

Or: pass to the inject method the values that we want sum to be initialized, in this case 0, and a second variable m as the method name.

  %w(negative positive neutral).inject(0) {|sum, m| sum + send(m) }
  # => 100

That’s all!