Georg Dresler

Tackling Complexity With Functional Programming And Kotlin

What if your type system could eliminate entire classes of runtime errors? Learn how functional patterns in Kotlin make illegal states unrepresentable, leading to more robust code.

Tackling Complexity With Functional Programming And Kotlin
#1about 3 minutes

Understanding a complex and unusual feature request

A real-world example of a complex feature request involves an offline form editor that syncs data via JSON embedded in PDF metadata.

#2about 3 minutes

Why traditional try-catch blocks fail for complex errors

Traditional try-catch blocks for error handling either obscure an error's origin or make the code unreadable with excessive boilerplate.

#3about 7 minutes

Using the Either type for robust functional error handling

Replace exceptions with the `Either` sealed class, using `flatMap` to chain successful operations and `fold` to handle the final success or error state.

#4about 4 minutes

Enforcing data validation using private constructors in Kotlin

Use a private constructor combined with a companion object's `invoke` operator to run validation logic upon object creation, preventing invalid states.

#5about 7 minutes

Modeling distinct data states with algebraic data types

Use sealed classes (sum types) to model different states like `Draft` and `Validated`, letting the compiler enforce state-specific logic instead of relying on boolean flags.

#6about 4 minutes

Recap of functional techniques and audience Q&A

A summary of using `Either` for errors, private constructors for validation, and ADTs for state, followed by a Q&A on libraries like Arrow and custom exceptions.

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Matching moments

Modern object orientation with Kotlin data classes
02:53 MIN

Modern object orientation with Kotlin data classes

Moving from Java to Kotlin

Using Kotlin Coroutines to simplify complex reactive code
09:38 MIN

Using Kotlin Coroutines to simplify complex reactive code

Back(end) to the Future: Embracing the continuous Evolution of Infrastructure and Code

Real-world applications of functional programming
13:51 MIN

Real-world applications of functional programming

A Guide To Functional Programming

Leveraging functional programming with first-class functions
06:50 MIN

Leveraging functional programming with first-class functions

Moving from Java to Kotlin

Audience Q&A on Kotlin features and learning resources
46:13 MIN

Audience Q&A on Kotlin features and learning resources

Route from Java to Kotlin

Creating reusable UI components with Kotlin extension functions
12:57 MIN

Creating reusable UI components with Kotlin extension functions

How to kill JavaScript from your Stack with HTMX and Kotlin

Audience Q&A on functional programming concepts
19:25 MIN

Audience Q&A on functional programming concepts

A Guide To Functional Programming

Introduction to Kotlin and its Java interoperability
00:02 MIN

Introduction to Kotlin and its Java interoperability

Route from Java to Kotlin

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