Introduction to programming with ZIO functional effects

1. Introduction to
Programming with
ZIO Functional Effects

2. JORGE VASQUEZ
SCALA DEVELOPER

3. Agenda
● Basic concepts about Functional Programming (FP)
● Basic concepts about ZIO
● Live coding: Hangman game

4. What is
Functional
Programming?

5. Programming with
Pure Functions!

6. Programming with
Pure Functions!
Total

7. def divide(a: Int, b: Int): Int = a / b
divide(5, 0)
// java.lang.ArithmeticException: / by zero

8. def divide(a: Int, b: Int): Option[Int] =
if (b != 0) Some(a/b) else None
divide(5, 0) // None

9. Programming with
Pure Functions!
Total
Deterministic

10. var a = 0;
def increment(inc: Int): Int = {
a += inc
a
}
increment(1) // 1
increment(1) // 2

11. def increment(a: Int)(inc: Int): Int = {
a + inc
}

12. Programming with
Pure Functions!
Total
Deterministic
No side-effects

13. But...
I need my
side-effects!

14. What
can we
do?

15. Functions that
describe
side-effects!

16. Enter

17. Composable
programming

18. Type-safe programming

19. Async and concurrent
programming

20. The ZIO data type
ZIO[-R, +E, +A]

21. ZIO data type Mental Model
R => Either[E, A]

22. ZIO Type Aliases
Task[+A] = ZIO[Any, Throwable, A]

23. ZIO Type Aliases
UIO[+A] = ZIO[Any, Nothing, A]

24. ZIO Type Aliases
RIO[-R, +A] = ZIO[R, Throwable, A]

25. ZIO Type Aliases
IO[+E, +A] = ZIO[Any, E, A]

26. ZIO Type Aliases
URIO[-R, +A] = ZIO[R, Nothing, A]

27. Live coding:
Hangman game
with ZIO

28. GitHub repo
https://github.com/jorge-vasquez-2301/zio-hangman

29. THANK YOU!

30. @jorvasquez2301
jorge.vasquez@scalac.io
jorge-vasquez-2301
Contact me