Disqus - Latest Comments for raulraja

Re: Well-Typed Reflections

Raúl Raja — Thu, 11 Oct 2018 16:02:36 -0000

This is inspiring. Thanks for the amazing write up and examples. I'm considering porting some of these ideas to Arrow in Kotlin. Intrigued as to what monoid comprehensions may look like in Kotlin. Cheers and Kudos!

Re: Java Optionals and Kotlin Nulls

Raúl Raja — Mon, 30 Oct 2017 19:08:49 -0000

Check out http://kategory.io/docs/dat... for a proper Option type that is safe and adheres to many useful type classes

Re: When old-school developer goes freestyle

Raúl Raja — Thu, 13 Jul 2017 18:06:41 -0000

Lech, thanks for the post and writting about Freeestyle.

Let me address some of your concerns here.

Regarding IDE support. All FP libs in Scala face the same issue. IntelliJ uses its own parser and not the presentation compiler. Most of the issues you mention are getting fixed as we speak though and libraries that use macro annotations such as Freestyle are getting full IDEA support and code completion as soon as this in progress branch gets merged and released in the new scala IDEA plugin: https://github.com/JetBrain... .

Freestyle also comes with `LoggingM` and other effects such as `OptionM` that you may use in place of transformers or nested for comprehensions like in the example in `login`. The code as described there is overly complicated as you would find when not using transformers or in this case effect algebras to deal with absence, error, logging and other common application concerns.

Regarding referring to all your algebras in the uber module, Freestyle can recurse down nested submodules so there is no need to include all of your algebras in your final module. Modules are recursive and when they find another module as dependency they recurse down until they find the Algebras at the leafs of the tree in your application.

You don't need to redefine `FS` in your helper classes. FS is a depedent type that points to the FreeApplicative and `import freestyle._` brings in implicit conversion that can automatically lift `FS` to its monadic representation in for comprehensions. For methods in helper classes where you are manually carrying over the `F[_]` constrain that refers to the manual Coproduct you may just have your methods return `FreeS[F, A]`.

When using for comprehensions with a single binding those are not needed because you may just use `map` instead.

As for the type annotations those are not a Freestyle artifact but probably the variance in your algebras or ADTs though I have not looked closely and attempted to compile the code yet.

If your code examples are open for improvement and you'd like some advice on how to better organize them perhaps with a follow up post or some corrections to this one let me know. I'd love to help.

Thanks again for writing about Freestyle.

Re: Free and tagless compared - how not to commit to a monad too early

Raúl Raja — Tue, 09 May 2017 11:39:01 -0000

Great article and comparison @Adam Warski . For what is worth and at the risk of shameless self promotion we are working on Freestyle http://frees.io/. It allows for both approaches and performs optimizations you don't get with the manual encoding including a faster Coproduct, automatic stack-safety for tagless, mixed composition of Free and Tagless and removal of all the associated boilerplate.

Re: Functional Error Handling

Raúl Raja — Mon, 20 Feb 2017 04:57:43 -0000

Thanks!

Re: Functional Error Handling

Raúl Raja — Sat, 18 Feb 2017 13:48:25 -0000

Thanks Philippe, I'll get those fixed as soon as I get to a computer.

Re: Doobie | Connecting To Database

Raúl Raja — Fri, 11 Nov 2016 17:04:58 -0000

See the Getting Started sample sbt file at http://tpolecat.github.io/d...

Re: FP for the average Joe - III - Applications as Coproducts of Free Algebras

Raúl Raja — Wed, 28 Sep 2016 19:35:39 -0000

Thanks! Cheers!

Re: FP for the average Joe - III - Applications as Coproducts of Free Algebras

Raúl Raja — Wed, 28 Sep 2016 13:20:30 -0000

Konstantin, thanks for the kind words and for catching the typo. I'll submit a fix soon. The issue with your composition is that you are parameterizing `Application2` to the actual smart constructor class and not the ADT ops. It should be `type Application2[A] = Coproduct[LogOp, C01, A]` instead of `type Application2[A] = Coproduct[LogOps, C01, A]`. That is why the interpreters can't align properly to match the application Coproduct.

Re: Scala Exercises

Raúl Raja — Sat, 16 Jul 2016 07:04:42 -0000

Thanks Jeff!

Re: Scala Exercises

Raúl Raja — Wed, 13 Jul 2016 16:16:54 -0000

You have to fill in all the blanks before running. If the issue still persist please take add an issue to https://github.com/scala-ex... thanks!

Re: Scala Exercises

Raúl Raja — Wed, 13 Jul 2016 16:13:50 -0000

There is many missing typeclasses and datatypes for cats that are not even in their documentation. Exercises for open source libraries is a work in progress. We are tracking all issues in the Github issue repository for each one of the content exercises. I recommend you post these concerns there so they can be properly addressed either by the maintainers or people that wish to collaborate on improving the exercises https://github.com/scala-ex... . thanks!

Re: Scala Exercises

Raúl Raja — Wed, 13 Jul 2016 16:09:41 -0000

Hi Jeff this should have been fixed

Re: Scala Exercises

Raúl Raja — Thu, 07 Jul 2016 20:50:34 -0000

It's an issue with the scala compiler. We just deployed a fix that works around it. Hopefully it works now. thanks!

Re: Scala Exercises

Raúl Raja — Thu, 07 Jul 2016 20:49:39 -0000

We just deployed a workaround for an issue with the scala compiler internal state

Re: Scala Exercises

Raúl Raja — Thu, 07 Jul 2016 20:45:46 -0000

It's a scala compiler issue. We just deployed a workaround

Re: Scala Exercises

Raúl Raja — Thu, 07 Jul 2016 20:01:55 -0000

Internal scala compiler issues, getting workaround as we speak

Re: Scala Exercises

Raúl Raja — Wed, 29 Jun 2016 04:55:41 -0000

Should be fixed now. Thanks!

Re: Scala Exercises

Raúl Raja — Wed, 29 Jun 2016 03:29:31 -0000

Hi Felix, feel free to submit an issue in Github and it will be considered as we add new functionality. Thanks!

Re: Std Lib | Ranges

Raúl Raja — Fri, 24 Jun 2016 11:04:22 -0000

We are going to add a dialog that allows you to share and continue once a section is completed. https://github.com/scala-ex...

Re: Scala Exercises

Raúl Raja — Fri, 24 Jun 2016 08:25:42 -0000

The exercise is now fixed and it uses Double.

Re: Scala Exercises

Raúl Raja — Thu, 23 Jun 2016 07:20:34 -0000

This is taken from the Shapeless Feature list and these are the examples used there. Feel free to send a PR a with improvements. Thanks!

Re: FP for the average Joe - II - ScalaZ Monad Transformers

Raúl Raja — Sun, 03 Jan 2016 18:48:33 -0000

Thanks @Prescott I'll get that fixed

Re: FP for the average Joe - I - ScalaZ Validation

Raúl Raja — Mon, 05 Oct 2015 04:52:45 -0000

@farid gutierrez True, it's for people getting introduced to Scala but also looking into getting acquainted with the more functional approach. After all Scala is a hybrid and many people stick with the basics and more OOP style.

Re: FP for the average Joe - I - ScalaZ Validation

Raúl Raja — Mon, 05 Oct 2015 04:50:18 -0000

@Alex T That is great question. You can certainly do that. The point of using Validation is that being an Applicative you get all the abstractions implemented there beyond the example shown here in this article. A few of them illustrated here: http://eed3si9n.com/learnin...