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BasicScala.sc

// Purpose: show scala basic features in terms of grammar, readability, shortness, easy translation from human to machine
// How many of you know a programming language?
// Opening with the fizzbuzz

for (i <- Range.inclusive(1, 16)) {
  println(
    if (i % 3 == 0 && i % 5 == 0) "FizzBuzz"
    else if (i % 3 == 0) "Fizz"
    else if (i % 5 == 0) "Buzz"
    else i
  )
}

// Values

"asd"
'a'

true
false

12

1.2
1.2F

12L

12: Byte
12: Short

-12

1 + 2
3 * 4

(3 + 0) * 9

4 / 2

9 / 3

9 / 2
4 / 3

9 / 2F
-4 / 3D

// Strings

'a' + 'b'

""

"aasdsdasdasd"

"ov ka stex?"

"""
  - ay pnduk?
  - mi asa tenc
"""

"asd" + "a3333333"

"a" == "a"
"a" == "b"

// Local Values and Variables

val a = 1

res16 + res17

a + 5
val b = a + 5

val a = 9
var vr = 8
vr = 9

val f = 5
val fl = 5L
val fll = 5: Long
val flll: Long = 5

val o = s"asd $fll"

// Tuples
// Allows un/grouping things together fast

(1, 2)

(true, o)

val t = (res12, o, '4')

t._1
t._2
t._3

val tt: (Int, Boolean) = (1, false)

val (mek, fols) = tt

mek
fols

// you need a way to move over elements
// tuples are examples of why programming with values is hard

val s = List(1, 2, 3, 4)

s(1)

s ++ s
s -- s

val ss = List(s, s)

ss(1)(2)

s.sum
s.head
s.tail

val tl = List((1, "mek"), (2, "erku"))

// A better list of tuples
val m = Map(1 -> "mek", 2 -> "erku")

// Loops
// do a foreach

var sum = 0
for (n <- s) sum += n
sum

var summ = 0
for (n <- Range(0, 101)) summ += n
summ

val indicies = List(2, 0, 1)
val values = List(5, 6, 7)
val nested = List(indicies, values)

var total_sum_ = 0
for (l <- nested; v <- l) total_sum_ += v
total_sum_

var tot_even_sum = 0
for (l <- nested; v <- l; if v % 2 == 0) tot_even_sum += v
tot_even_sum

val onetoten = for (n <- Range(0, 10)) yield n
onetoten.sum

{ for {n <- Range(0, 5)} yield n }.sum
{5} // expression based

val nine = {8;9}

for {
  l <- nested; 
  v <- l; 
  if v % 2 == 0
} tot_even_sum += v

tot_even_sum

// side effects are one more thing to track

// Functions
// who heard about functions

8.5 * 8.5
8.5 * 8.5
8.5 * 8.5
8.5 * 8.5
8.5 * 8.5

val konkret_tiv = 9

konkret_tiv * konkret_tiv
konkret_tiv * konkret_tiv
konkret_tiv * konkret_tiv
konkret_tiv * konkret_tiv
konkret_tiv * konkret_tiv

konkret_tiv * konkret_tiv * konkret_tiv 
konkret_tiv * konkret_tiv * konkret_tiv 
konkret_tiv * konkret_tiv * konkret_tiv 
konkret_tiv * konkret_tiv * konkret_tiv 
konkret_tiv * konkret_tiv * konkret_tiv 

def hashvark(voreve_tiv: Int) = voreve_tiv * voreve_tiv * voreve_tiv
hashvark(konkret_tiv)

def printHello = println("Hello")
printHello

// Round braces are not needed, Scala tried to help you type less

def greet(greeting: String): Unit = println(greeting)
greet("Hi")

def greetNTimes(greeting: String, times: Int): Unit = for (i <- Range(0, times)) println(greeting)
greetNTimes("Ahoj", 3)

def greetNTimess(greeting: String, times: Int): Unit = for (_ <- Range(0, times)) println(greeting)
greetNTimes("Ahoj", 3)

def greetNTimesWD(greeting: String, times: Int = 1): Unit = for (i <- Range(0, times)) println(greeting)
greetNTimesWD("Ola")

def greetNTimesWDD(times: Int = 1, greeting: String): Unit = for (i <- Range(0, times)) println(greeting)
greetNTimesWDD(greeting = "Ola")

// The return type is optional but good practice
def add(a: Int, b: Int): Int = a + b
add(1, 2)

val addl: (Int, Int) => Int = (a, b) => a + b
addl(1, 2)

def uhashvark(voreve_tiv: Int)(voreve_ayl_tiv: Int)(ayl_voreve_tiv: Int): Int = voreve_tiv * voreve_ayl_tiv * ayl_voreve_tiv

val mas_1 = uhashvark(7)
val mas_2 = mas_1(2)
mas_2(5)

val uhashvarkl: Int => Int => Int => Int = 
  voreve_tiv => voreve_ayl_tiv => ayl_voreve_tiv => voreve_tiv * voreve_ayl_tiv * ayl_voreve_tiv

val umas_1 = uhashvarkl(7)
val umas_2 = mas_1(2)
umas_2(5)

// Classes
// a better tuple / product type

("Vanilla/Strawberry", 5)
("Cinnamon/Chocolate", 7)

class Marojni(val name: String, val price: Int)

val vs = Marojni("Vanilla/Strawberry", 5)
vs.name
val cc = Marojni("Cinnamon/Chocolate", 7)
cc.price

// Thank you

Inspired by the Hands-on Scala Programming