Careeroza

in, Range and Bitwise Operators

in and !in

Example

in checks whether a value is inside a range or a collection.

fun main() {
    val hour = 14
    println(hour in 9..21)                   // restaurant open?
    val city = "Pune"
    val serviceable = listOf("Pune", "Mumbai", "Delhi")
    println(city in serviceable)
    println("Goa" !in serviceable)
    println('k' in 'a'..'z')
}

Output

true
true
true
true

Bitwise Operations

Example

Kotlin has no &, |, << symbols for integers. It uses named infix functions instead: and, or, xor, inv(), shl, shr, ushr.

fun main() {
    val read = 0b001
    val write = 0b010
    val exec = 0b100
    val perms = read or write
    println(perms)                    // 3
    println(perms and write != 0)     // has write permission?
    println(perms and exec != 0)
    println(1 shl 4)                  // 16
    println(64 shr 2)                 // 16
    println(5 xor 3)                  // 6
}

Output

3
true
false
16
16
6

Note: Bitwise operations are used for flags, for example Android Intent flags and view gravity.

Operator Precedence

Priority (high to low)Operators
Postfixx++, x--, ., ?., !!
Prefix-x, ++x, !
Multiplicative*, /, %
Additive+, -
Range.., ..<
Infix functionsshl, and, until, to...
Elvis?:
Named checksin, !in, is
Comparison<, >, <=, >=
Equality==, !=, ===
Logical&& then ||
Assignment=, +=...

Tip: When in doubt, add parentheses. (a + b) * c is easier to read than relying on precedence.