Two Ruby Memoization Patterns

Two main memoization patterns I’ve seen are the following

# Example 1
def momoize_it
    @the_thing ||= ThingClass::get()

# Example 2
def memoize_it
  return @the_thing if defined?(@the_thing)
  @the_thing = ThingClass::get()

Example #1 is shorter, however if you stare at it hard enough you’ll realize if @the_thing is supposed to be false or a falsy value then it would never be memoized. Example #2 of checking if the variable has been defined is a more sure method of memoization, unless whats defined can’t be falsy.

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