The document discusses converting code from object-oriented programming to functional programming, focusing on concepts like immutability, recursion, and composition. It highlights common functional programming techniques like mapping, filtering, reducing, and list comprehensions. The document also provides references for learning more about functional programming in Clojure, Haskell, F#, and other languages.

1. The Functional
converter project

2. About me
@abarylko / @amirci
Software consultant
Entrepreneur
Employee
Living in California

5. Disappointment
Management

6. Converting to
Functionalfrom OOP

7. State
&
Classes
Recursion
Immutability
Composition
lambda

8. Bread & Butter
What is the most common construct?

9. Immutability

10. Returns always a
copy

11. No
more
state

12. What about
efficiency?

13. Persistent
CollectionsShared structure and thread safe

14. REPL Time!

15. Loops

16. Recursion is our
friend

17. TCO
Tail Call Optimization

18. REPL Time!

19. List
Comprehensions

20. Construct
•Based on other lists
•Map
•Filter
•Combine

21. REPL Time!

22. Idioms & Recipes

23. Custom loops woes

24. Every lang has it
;; Clojure
(map inc (range 1 20))
-- Haskell
map (+ 1) [1..20]
// F#
List.map ((+) 1) [1; 2; 3; 4]
// Java Part of `Stream` API
Arrays.asList(1, 2, 3, 4, 5).stream().map(i -> i + 1);
// C# Using LINQ extension methods
new List<int>() { 1, 2, 3, 4, 5 }.Select(i => i + 1);

25. Tools in your belt
Mapping
Filtering
Concatenation
Taking & Dropping
Reduce
Zipping
Group
Frequencies
Iterate/Unfold
Partition

26. REPL Time!

27. Thank you!

28. References
Coding Rehab - http://codingrehab.com
Clojure for the brave and true - https://www.braveclojure.com
Learn you a Haskell - http://learnyouahaskell.com/
F# for fun and profit - https://fsharpforfunandprofit.com/

29. @abarylko
@amirci