Scalaz is a library for Scala that enables pure functional programming. It uses type classes and higher order functions instead of subtyping. Scalaz comes with many built-in type classes like Equal, Order, Enum, Options, and Validation. It also encourages building custom type classes. The presentation introduces Scalaz and some of its core type classes. It provides examples of problems in non-functional code that Scalaz can solve through its approach.

1. Introduction to ScalaZ
Prabhat Kashyap
Trainee Software Consultant
Knoldus Software LLP

2. What is Scalaz
● It is just another library for Scala.

3. What is Scalaz
● It is just another library for Scala.
● Scalaz is purely functional library.

4. What is Scalaz
● It is just another library for Scala.
● Scalaz is purely functional library.
● It provides new functions.

5. What is Scalaz
● It is just another library for Scala.
● Scalaz is purely functional library.
● It provides new functions.
● It’s an open source project
(https://github.com/scalaz/scalaz)

6. Why new library?

7. Whats wrong with this code:
val internInProject = Map(
"Prabhat" -> "ScalaGeek",
"Kunal" -> "FitFyles",
"Himani" -> "FitFyles"
)
def isInternFromProject(project: String, intern:
String): Boolean =
(internInProject get intern) == project

8. Whats wrong with this code:
val internInProject = Map(
"Prabhat" -> "ScalaGeek",
"Kunal" -> "FitFyles",
"Himani" -> "FitFyles"
)
def isInternFromProject(project: String, intern:
String): Boolean =
(internInProject get intern) == project
== is not typesafe here
IsInternFromProject will always return false

9. Let’s try one more
val intern1 = Map(
"Prabhat" -> Map("scalageek" -> 10, "FitFyles" -> 1),
"Aarwee" -> Map("FitFyles" -> 6, "ScalaGeek" -> 3),
"Deepti" -> Map("FitFyles" -> 11)
)
val intern2 = Map(
"Prabhat" -> Map("scalageek" -> 3)
)
Now you can write a complex code with map functions

10. Let’s try one more
val intern1 = Map(
"Prabhat" -> Map("scalageek" -> 10, "FitFyles" -> 1),
"Aarwee" -> Map("FitFyles" -> 6, "ScalaGeek" -> 3),
"Deepti" -> Map("FitFyles" -> 11)
)
val intern2 = Map(
"Prabhat" -> Map("scalageek" -> 3)
)
Or you can use |+|
val combinedResult = (intern1 |+| intern2)

11. Let’s try one more
val intern1 = Map(
"Prabhat" -> Map("scalageek" -> 10, "FitFyles" -> 1),
"Aarwee" -> Map("FitFyles" -> 6, "ScalaGeek" -> 3),
"Deepti" -> Map("FitFyles" -> 11)
)
val intern2 = Map(
"Prabhat" -> Map("scalageek" -> 3)
)
Or you can use |+|
val combinedResult = (intern1 |+| intern2)
Map(
"Prabhat" -> Map("scalageek" -> 13, "FitFyles" -> 1),
"Aarwee" -> Map("FitFyles" -> 6, "ScalaGeek" -> 3),
"Deepti" -> Map("FitFyles" -> 11))
And Combined Result will be

12. Why ScalaZ
● Scalaz is a library for doing pure Functional
Programming in Scala.

13. Why ScalaZ
● Scalaz is a library for doing pure Functional
Programming in Scala.
● Scalaz does not encourage subtyping—instead it
espouses typeclass-based ad hoc polymorphism
using higher order functions.

14. Why ScalaZ
● Scalaz is a library for doing pure Functional
Programming in Scala.
● Scalaz does not encourage subtyping—instead it
espouses typeclass-based ad hoc polymorphism
using higher order functions.
● Scalaz comes with a lot of built in typeclasses and
encourages you to build your own.

15. Today we only be looking at
Scalaz Typeclasses

16. ScalaZ Typeclasses
● Equal[A] typeclass

17. ScalaZ Typeclasses
● Equal[A] typeclass
● Order

18. ScalaZ Typeclasses
● Equal[A] typeclass
● Order
● Enum

19. ScalaZ Typeclasses
● Equal[A] typeclass
● Order
● Enum

20. ScalaZ Typeclasses
● Equal[A] typeclass
● Order
● Enum
● Options

21. ScalaZ Typeclasses
● Equal[A] typeclass
● Order
● Enum
● Options

22. ScalaZ Typeclasses
● Equal[A] typeclass
● Order
● Enum
● Options
● Validation

23. ScalaZ Typeclasses
● Equal[A] typeclass
● Order
● Enum
● Options
● Validation

24. Questions?

25. References
● Wikipedia
● http://eed3si9n.com/
● Youtube
– Scalaz Presentation - Nick Partridge
– Introduction to Scalaz - Heiko Seeberger

26. Thanks