Power of Functions in a Typed World on the JVM

schedule Dec 13th 11:30 AM - 01:00 PM place Crystal 1 people 10 Interested

John Carmac once mentioned on twitter that "Sometimes, the elegant implementation is just a function. Not a method. Not a class. Not a framework. Just a function." In this talk we will discuss the power of functions in modeling real world applications on the JVM. When we say functions, we mean "pure" functions as in the world of mathematics.

Functions model behaviors, functions compose to build larger functions, and combined with a powerful type system allow us to abstract over the generalities in defining real world domain models. The combination of functions along with algebraic data types has proven to be extremely useful in designing large scale systems that are modular and extensible.

Scala is a typed functional (well, almost) language on the JVM. In this session we will discuss how the functional features of Scala offer many of the above benefits in designing large scale systems. If you are coming from an OO background, you will appreciate how an alternative approach to programming can make your systems simpler to design, implement and maintain.

 
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Outline/structure of the Session

  1. Introduce the benefits of pure functions
  2. Introduce Scala
  3. Discuss the powers of compositionality of functions
  4. From OO to FP - how to make the jump
  5. Introduce Algebraic Data Types (ADT)
  6. Thinking in terms of functions + ADTs
  7. Algebra is all you need
  8. A brief explanation of how to handle side-effects algebraically
  9. Modularity in a functionally designed system

Learning Outcome

I expect attendees to develop an appreciation of typed functional programming on the JVM

Target Audience

Beginners who would like to jump into the FP bandwagon

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