# Javascript Operators

From Elite Wiki

## Contents

## Operators used in Javascript

Below is a listing of often used operators in javascript to help understand some of the used code in Oolite scripts. A quick introduction and further links can be found in Scripting Oolite with JavaScript.

### Arithmetic Operators

**Operator Description**

+ Addition

- Subtraction

* Multiplication

/ Division

% Modulus (remainder of a division)

++ Increment (++X means increment by one X before use and X++ means increment X after use

-- Decrement (--X means idecrement by one X before use and X-- means decrement X after use

### Assignment Operators

**Operator Description**

= Assign

+= Add and assign. For example, x+=y is the same as x=x+y.

-= Subtract and assign. For example, x-=y is the same as x=x-y.

*= Multiply and assign. For example, x*=y is the same as x=x*y.

/= Divide and assign. For example, x/=y is the same as x=x/y.

%= Modulus and assign. For example, x%=y is the same as x=x%y.

### Comparison Operators

**Operator Description**

== Is equal to

=== Is identical (is equal to and is of the same type)

!= Is not equal to

!== Is not identical

> Greater than

>= Greater than or equal to

< Less than

<= Less than or equal to

### Logical/boolean Operators

**Operator Description**

&& and

|| or

! not

### String Operators

In JavaScript, a string is simply a piece of text.

**Operator Description**

= Assignment

+ Concatenate (join two strings together)

+= Concatenate and assign

### Bit Operators

**Operator Description**

& Bitwise and

| Bitwise or

^ Bitwise exclusive or (xor)

~ Flip all bits (invert 0 to 1 and 1 to 0)

Bitshifting operation converts to 32-bit integers, big-endian order and returns a result of the same type as the left operand.

<< Shift bits to the left (9 << 2 yields 36)

>> Shift bits to the right, keep sign (9 >> 2 yields 2 BUT -9 >> 2 yields -3)

>>> Shift bits to the right, discard sign bit (9 >>> 2 yields 2 BUT -9 >>> 2 yields 1073741821)