OPERATORS

In programming, operators are symbols or characters that perform specific actions on values or variables. They allow you to manipulate and perform calculations on data in your program.

There are 4 types of operators:
(1) Arithmetic (addition, subtraction, etc.)
(2) Comparison (greater than, less than, etc.)
(3) Logical (manipulate conditions)
(4) Bitwise (manipulate bits in binary data)

There is one extra operator for concatenation, combining a string with other values into a longer string: (..)

a = "hello"
b = "world"
print( a .. " " .. b ) --hello world

Arithmetic Operators

These are used to manipulate numbers and perform basic mathematical operations.

--addition
3+2 --5

--subtraction
8-2 --6

--multiplication
7*3 --21

--division
40/5 --6

--modulo
10%7 --3

--exponentiation
4^3 --64

Comparative Operators

These are used to manipulate values (usually numbers) and perform basic comparisons between two values, usually in an if statement.

if a==b then print("equal") end

if a~=b then print("not equal") end

if a!=b then print("not equal") end

if a<b then print("greater than") end

if a<=b then print("less than or equal") end

if a>=b then print("greater than or equal") end

The equal and not equal comparison works with numbers, strings, booleans, and functions.

Logical Operators

These are used to manipulate or compare values (usually booleans). All logical operators consider both false and nil as false and anything else as true.

and

--booleans
print( true and true )   --true
print( true and false )  --false
print( false and true )  --false
print( false and nil )   --false
--numbers
print( 10 and 3 )        --3
print( nil and 3 )       --nil
--strings
print( "a" and "b" )     --b
print( "a" and nil )     --nil

or

--booleans
print( false or false ) --false
print( true or false )  --true
print( false or true )  --true
print( false or nil )   --nil
--numbers
print( 10 or 3 )        --10
print( nil or 3 )       --3
--strings
print( "a" or "b" )     --a
print( nil or "b" )     --b

not

--booleans
print( not true )    --false
print( not false )   --true
--numbers
print( not -3 )      --false
print( not 0 )       --false
--strings
print( not "b" )     --false
--nil
print( not nil )     --true

A common way to use these logical operators is to combine multiple condition checks, for example:

if a and b then
	print("both true")
end

if a or b then
	print("one or both true")
end

if not a and b or c then
	print("it's complicated")
end

Bitwise Operators (advanced)

See Bitwise Operations for more.

Precedence of Operators

Operator precedence determines the order in which operators are evaluated in an expression. It ensures that expressions are evaluated in a consistent and predictable manner. When multiple operators are used in a single expression, operator precedence helps determine which operators are evaluated first.

highest precedence

lowest precedence