a9.operators.md

title: Operators

• Arithmetic Operators

+ - * / %

let a = 5;
let b = a + 1; //6
let c = a - 1; //4
let d = a * 2; //10
let e = a / 2; // ⭐️ 2 not 2.5
let f = a % 2; //1

let g = 5.0 / 2.0; //2.5

• Comparison Operators

== != < > <= >=

let a = 1;
let b = 2;

let c = a == b; //false
let d = a != b; //true
let e = a < b; //true
let f = a > b; //false
let g = a <= a; //true
let h = a >= a; //true

// 🔎
let i = true > false; //true
let j = 'a' > 'A'; //true

• Logical Operators

! && ||

let a = true;
let b = false;

let c = !a; //false
let d = a && b; //false
let e = a || b; //true

🔎 On integer types,! inverts the individual bits in the two’s complement representation of the value.

let a = !-2; //1
let b = !-1; //0
let c = !0; //-1
let d = !1; //-2

• Bitwise Operators

& | ^ << >>

let a = 1;
let b = 2;

let c = a & b;  //0  (01 && 10 -> 00)
let d = a | b;  //3  (01 || 10 -> 11)
let e = a ^ b;  //3  (01 != 10 -> 11)
let f = a << b; //4  (Add b number of 0s to the end of a -> '01'+'00' -> 100)
let g = a >> b; //0  (Remove b number of bits from the end of a -> o̶1̶ -> 0)

• Assignment and Compound Assignment Operators

The = operator is used to assign a name to a value or a function. Compound Assignment Operators are created by composing one of + - * / % & | ^ << >> operators with = operator.

let mut a = 2;

a += 5; //2 + 5 = 7
a -= 2; //7 - 2 = 5
a *= 5; //5 * 5 = 25
a /= 2; //25 / 2 = 12 not 12.5
a %= 5; //12 % 5 = 2

a &= 2; //10 && 10 -> 10 -> 2
a |= 5; //010 || 101 -> 111 -> 7
a ^= 2; //111 != 010 -> 101 -> 5
a <<= 1; //'101'+'0' -> 1010 -> 10
a >>= 2; //101̶0̶ -> 10 -> 2

• Type Casting Operator

as

let a = 15;
let b = (a as f64) / 2.0; //7.5

• Borrowing and Dereference Operators

& &mut *

🔎 The & or &mut operators are used for borrowing and * operator for dereferencing. For more information, refer Ownership, Borrowing & Lifetimes sections.

Before going to the next...

• About string concatenation,

let (s1, s2) = ("some", "thing"); // both &str
// All bellow codes return `String`; something

let s = String::from(s1) + s2; // String + &str

let mut s = String::from(s1); // String
s.push_str(s2); // + &str

let s = format!("{}{}", s1, s2); // &str/String + &str/String

let s = [s1, s2].concat(); // &str or Sting array