alexwayfer / alt_memery Goto Github PK

gem "alt_memery", "~> 2.1", require: "memery"

This gem has a different name for the primary entry point than bundler expects. Two options are to add an alt_memery.rb which loads memery, or update README with instruction like above.

Is all of this expected, intentional? Just want to manage my expectations when using the library.

require 'bundler/inline'

gemfile do
  source 'https://rubygems.org'
  gem 'alt_memery', require: false
end

require "memery"

class A
  include Memery

  memoize def call(time = Time.now)
      puts "called at #{time}"
      42
  end
end

a = A.new
puts "Call 1 (use default)"
a.call
puts "Call 1 (use default) Done\n\n"
sleep(1)
puts "Call 2 (use default)"
a.call
puts "Call 2 (use default) Done\n\n"
sleep(1)
puts "Call 3 (Time.now)"
a.call(Time.now)
puts "Call 3 (Time.now) Done\n\n"
sleep(1)
puts "Call 4 (Time.now 2nd)"
a.call(Time.now)
puts "Call 4 (Time.now 2nd) Done\n\n"
sleep(1)
puts "Call 5 (Time.new(2002))"
a.call(Time.new(2002, 10, 31, 2, 2, 2, "+02:00"))
puts "Call 5 (Time.new(2002)) Done\n\n"
sleep(1)
puts "Call 6 (Time.new(2002) 2nd)"
a.call(Time.new(2002, 10, 31, 2, 2, 2, "+02:00"))
puts "Call 6 (Time.new(2002) 2nd) Done\n\n"

And here's the output:

Call 1 (use default)
called at 2024-01-12 17:23:48 +0700
Call 1 (use default) Done

Call 2 (use default)
Call 2 (use default) Done

Call 3 (Time.now)
called at 2024-01-12 17:23:50 +0700
Call 3 (Time.now) Done

Call 4 (Time.now 2nd)
called at 2024-01-12 17:23:51 +0700
Call 4 (Time.now 2nd) Done

Call 5 (Time.new(2002))
called at 2002-10-31 02:02:02 +0200
Call 5 (Time.new(2002)) Done

Call 6 (Time.new(2002) 2nd)
Call 6 (Time.new(2002) 2nd) Done

To summarize...

The following calls w/ arguments are memoized, such that when called again they are not re-executed:

1. Default argument value is Time.now, which normally in Ruby is evaluated fresh on every call, but with memoization it is not. This is the same behavior as some other memoization libraries, and maybe it has to be this way...

a.call

2. When the Time argument is representing the same time as a previous call, the memoized result is used. This is cool.

a.call(Time.new(2002, 10, 31, 2, 2, 2, "+02:00"))

The following calls w/ arguments are not memoized, such that when called again they are freshly executed each time called:

a.call(Time.now)

Tested on Ruby 3.2.2

ref: https://stackoverflow.com/questions/53783291/ruby-default-arguments-static-or-dynamic

Clear caches only for specific methods.

After #93 I assumed I understood how it would behave when memoizing methods with parameters that are complex objects (like the Time objects in that example). My hope that that it would follow the same "identity" comparison that Rails uses to know that two ActiveRecord objects are the same, but that is not the case, as the methods are called repeatedly with the same object being passed every time.

Going to poke around in the source code for a while to look for an easy way to hack a solution.