sums_up VS daggy

Now with Ruby we have a few different ideas we want to express. Whereas Daggy has tagged and taggedSum we have Struct and SumsUp.define instead. You can find more info on SumsUp here, but we'll be covering the general details in this post.

Hello, r/ruby! I wrote a gem, sums_up, for defining and pattern matching against sum types at Ruby. This isn't the first attempt at porting sum types into the language, but the other implementations that I've used either didn't "feel like" traditional Ruby, or didn't "feel like" a native sum type implementation. I tried my best to bridge that gap. Code Sample: ‏‏‎ require 'sums_up' # Define a sum type for Users; they can either be anonymous or logged in. User = SumsUp.define(:anonymous, logged_in: :email) # => User anon = User.anonymous # => # logged_in = User.logged_in('[email protected]') # => # anon.anonymous? # => true anon.logged_in? # => false logged_in.anonymous? # => false logged_in.logged_in? # => true anon.email # => NoMethodError: undefined method `email' for # logged_in.email # => "[email protected]" def valid_email?(user) user.match do |m| m.anonymous false m.logged_in { |email| URI::MailTo::EMAIL_REGEXP.match?(email) } end end valid_email?(anon) # => false valid_email?(logged_in) # => true valid_email?(User.logged_in('1337h@ck3r')) # => false There are a few more thorough examples in the README. If you're interested, try it out and let me know what you think!

The initial post that we're working from is the introduction into both data classes and sum types using Daggy, and you can read the original post here: