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Complementing exceptions - Introducing monads for error handling in ruby

Cherry Ramatis on August 13, 2023

Have you ever considered your approach to handling exceptions? I'm referring to the method in which you use the raise keyword within a class, and t...

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Hartmut B. • Sep 24 '23

Thanks for this comprehensive summary.
I looked at ChatGBT for DRY::Monads. The answer focuses mostly on aspects of functional programming. Then I understood, why you used the unusual A.new.call approach in your examples.
I translated your first example to (to me) familar ruby

class Auth
  extend Dry::Monads[:result]
  def self.authenticate name
      name == 'correct' ?  Success( name: name) : Failure( error: "No such User") 
  end
end

r= A.authenticate( 'somone' ) 
r.success?

Now the approach behaves much more like a state machine then a variation of error-handling.

Hartmut B. • Sep 25 '23

A second observation.

your example

class Runner
  include Dry::Monads::Do.for(:call)

  def call
    value = Auth.new.authenticate(name: 'incorrect')

    return value.failure if value.failure?

    yield value
  end
end

does work. However, the returnstatement is not needed.
If you try the example without it and run into Failure, the statement Runner.new.callsimply returns the Dry::Monad::Result::Failure object.
Check it out!

Cherry Ramatis • Sep 25 '23

I honestly prefer the return for legibility reason, but it's cool if we don't need it

Cherry Ramatis • Sep 24 '23

Amazing incrementing to this article! Thanks a lot

Italo • Aug 13 '23

Qualidade demais Cherry👏👏👏

Cherry Ramatis • Aug 13 '23

Muito obrigada primo!

Canhassi • Aug 14 '23

muito brabo!

Renan Vidal Rodrigues • Aug 14 '23

Excellent article! It's always amazing to read!

Cherry Ramatis • Aug 14 '23

Thanks for the kind words cousin <3

Gustavo • Aug 15 '23

Didática e conteúdos muito bons!!!! Manda demais prima!!

Cherry Ramatis • Aug 15 '23

Mto obrigada primo <3

Kudzai Murimi • Aug 18 '23

Well Explained hey ! Excellent

Cherry Ramatis • Aug 18 '23

Thanks a lot 🩷

João Victor • Aug 13 '23

Faço um uso parecido no TS com o effect, fica lindo demais

Cherry Ramatis • Aug 13 '23

Uma das inspirações foram essas implementações no typescript, não conheço explicitamente o effect, mas realmente funciona super bem

SamucaDev • Aug 15 '23

Amazing, the queen of vim!

Cherry Ramatis • Aug 15 '23

Thanks a lot cousin <3

Ilo Navarro • Aug 15 '23

Show!

Foxgeeek • Aug 15 '23

Cualidad!

Cherry Ramatis • Aug 15 '23

ty <3

JuanBoice • Aug 16 '23

Excellent article. Thanks a good article shared with us. witchcraft love spells

Hewerton Soares • Aug 15 '23

Sá salvei pra ler mais tarde, muito bom o conteúdo!!

Cherry Ramatis • Aug 15 '23

Muito obrigada primo

oChefDev • Aug 15 '23

Nice article.

Cherry Ramatis • Aug 15 '23

Ty <3

Pedro Henrique • Aug 15 '23

Cherry... você é sensacional, prima <3

Cherry Ramatis • Aug 15 '23

O que eu puder fazer por todo mundo é sempre um prazer, brigada pelo apoio primo