operators

types of operators: 1- Assignment operators

• assigns a value to its left operand (=)
• Addition assignment x += y
• Subtraction assignment x -= y
• Multiplication assignment x *= y
• Division assignment x /= y
• Remainder assignment x %= y
• Exponentiation assignment x **= y
• Left shift assignment x «= y
• Right shift assignment x »= y
• Unsigned right shift assignment x »>= y
• Bitwise AND assignment x &= y
• Bitwise XOR assignment x ^= y

• Bitwise OR assignment x

  = y

• Logical AND assignment x &&= y

• Logical OR assignment x

  = y

• Logical nullish assignment x ??= y

The return value matches the expression to the right of the = sign

2- Comparison operators A comparison operator compares its operands and returns a logical value Equal (==)Not equal (!=) Strict equal (===)Strict not equal (!==)Greater than (>) Greater than or equal (>=) Less than (<) Less than or equal (<=) 3- Arithmetic operators The standard arithmetic operators are addition (+), subtraction (-), multiplication (*), and division (/) Remainder (%)Increment (++)Decrement (–)Unary negation (-)Unary plus (+)Exponentiation operator (**)

4- Bitwise operators Bitwise AND a & b Bitwise OR a | b Bitwise XOR a ^ b Bitwise NOT ~ a Left shift a « b Sign-propagating right shift a » b Zero-fill right shift a »> b

5- Logical operators Logical AND (&&) Logical OR (||) Logical NOT (!) 6- String operators the concatenation operator (+) concatenates two string values together,The shorthand assignment operator += can also be used to concatenate strings. 7- Conditional (ternary) operator takes three operands The operator can have one of two values based on a condition. The syntax: condition ? val1 : val2 If condition is true, the operator has the value of val1. Otherwise it has the value of val2. 8- Comma operator

9- Unary operators delete typeof operator returns a string indicating the type The void operator specifies an expression to be evaluated without returning a value

10- Relational operators -The in operator returns true if the specified property is in the specified object -The instanceof operator returns true if the specified object is of the specified object type

Operator precedence :

The precedence of operators determines the order they 	are applied when evaluating an expression
member	. []
call / create instance	() new

JavaScript has both binary and unary operators, and one special ternary operator, the conditional operator. A binary operator requires two operands, one before the operator and one after the operator

A unary operator requires a single operand, either before or after the operator:

this refers to the calling object in a method.

Grouping operator The grouping operator ( ) controls the precedence of evaluation in expressions

new You can use the new operator to create an instance of a user-defined object type or of one of the built-in object types

super The super keyword is used to call functions on an object’s parent. It is useful with classes

Loops and iteration

Loops offer a quick and easy way to do something repeatedly.

The statements for loops provided in JavaScript are:

1- for statement :A for loop repeats until a specified condition evaluates to false for ([initialExpression]; [conditionExpression]; [incrementExpression]) {statement}

2- do…while statement : The do…while statement repeats until a specified condition evaluates to false. syntax : do statement while (condition); statement is always executed once before the condition is checked

3- while statement :A while statement executes its statements as long as a specified condition evaluates to true syntax : while (condition) { statement} If the condition becomes false, statement within the loop stops executing and control passes to the statement following the loop.

4- labeled statement :A label provides a statement with an identifier that lets you refer to it elsewhere in your program. you can use a label to identify a loop, and then use the break or continue statements to indicate whether a program should interrupt the loop or continue its execution. syntax : label : statement

5- break statement :Use the break statement to terminate a loop, switch, or in conjunction with a labeled statement.

6- continue statement :The continue statement can be used to restart a while, do-while, for, or label statement.

7- for…in statement :The for…in statement iterates a specified variable over all the enumerable properties of an object. syntax : for (variable in object) statement

8- for…of statement :The for…of statement creates a loop Iterating over iterable objects (including Array, Map, Set, arguments object and so on), invoking a custom iteration hook with statements to be executed for the value of each distinct property.