Is there a convention for memoization in a method call?

Question

I want to avoid reevaluation of a value in method call. Untill now, I was doing this:

def some_method
  @some_method ||= begin
    # lot\'s of code
  end
end
         


        

Answer 1

I normally do it like in Agis answer or:

def filesize() @filesize ||=
  calculate_filesize
end

BTW:

I often use this memoization technique:

def filesize() @_memo[:filesize] ||=
  calculate_filesize
end

Which will allow you to later clear all memoized variables with one simple @_memo.clear. The @_memo variable should be initialized like this Hash.new { |h, k| h[k] = Hash.new }. It gives you many of the adventages of using ActiveSupport::Memoize and similar meta programmed techniques which might be much slower.