Memoized

Memoized will memoize the results of your methods. It acts much like ActiveSupport::Memoizable without all of that freezing business. The API for unmemoizing is also a bit more explicit.

$ gem install memoized

To define a memoized instance method, use memoize def:

class A
  include Memoized

  memoize def hello
    'hello!'
  end
end

You may also memoize one or more methods after they have been defined:

class B
  include Memoized

  def hello
    'hello!'
  end

  def goodbye
    'goodbye :('
  end

  memoize :hello, :goodbye
end

Memoizing class methods works the same way:

class C
  class << self
    include Memoized

    memoize def hello
      'hello!'
    end
  end
end

To unmemoize a specific method:

instance = A.new
instance.hello              # the hello method is now memoized
instance.unmemoize(:hello)  # the hello method is no longer memoized
instance.hello              # the hello method is run again and re-memoized

To unmemoize all methods for an instance:

instance = B.new
instance.hello          # the hello method is now memoized
instance.goodbye        # the goodbye method is now memoized
instance.unmemoize_all  # neither hello nor goodbye are memoized anymore

When you are using Memoized with default arguments or default keyword arguments, there are some edge cased you have to keep in mind.

When you memoize a method with (keyword) arguments that have an expression as default value, you should be aware that the expression is evaluated only once.

memoize def print_time(time = Time.now)
  time
end

print_time
=> 2021-07-23 14:23:18 +0200

sleep(1.minute)
print_time
=> 2021-07-23 14:23:18 +0200

When you memoize a method with (keyword) arguments that have default values, you should be aware that Memoized differentiates between a method call without arguments and the default values.

def true_or_false(default = true)
  puts 'calculate value ...'
  default
end

true_or_false
calculate value ...
=> true

true_or_false
=> true

true_or_false(true)
calculate value ...
=> true

I'm very eager to keep this gem leightweight and on topic. If you're unsure whether a change would make it into the gem, talk to me beforehand.

There are tests in spec. We only accept PRs with tests. If you create a PR, the tests will automatically run on GitHub actions on each push. We will only merge pull requests after a green GitHub actions run.

To run tests locally for development you have multiple options:

1. Run tests against a specific Ruby version:

   • Install and switch to the Ruby version
   • Install development dependencies using bundle install
   • Run tests using bundle exec rspec

2. Run tests against all Ruby versions:

   • Install all Ruby versions mentioned in .github/workflows/test.yml
   • run bin/matrix (only supports rbenv for switching Ruby versions currently)

Hints:

• At the time of writing this, we only have a single Gemfile. If that isn't the case any longer, check the gemika README for more detailed development instructions.
• We recommend to have sufficiently new versions of bundler (> 2.3.0) and rubygems (> 3.3.0) installed for each Ruby version.
• The script bin/matrix will warn you, if that is not the case. For all other methods you need to ensure that yourself.

See LICENSE.txt

• This gem is a fork of Memoizer by Wegowise.
• Changes in this fork by makandra.