Basic Operators

An operator is a special symbol or phrase that you use to check, change, or combine values. For example, the addition operator (+) adds two numbers, as in const i = 1 + 2, and the logical AND operator (&&) combines two Boolean values, as in if isPrime && isEven.

LichenScript supports the operators you may already know from languages like JavaScript. The assignment operator (=) doesn’t return a value, to prevent it from being mistakenly used when the equal to operator (==) is intended.

Assignment Operator

The assignment operator (a = b) initializes or updates the value of a with the value of b:

const b = 10
let a = 5
a = b
// a is now equal to 10

Arithmetic Operators

LichenScript supports the four standard arithmetic operators for all number types:

  • Addition (+)
  • Subtraction (-)
  • Multiplication (*)
  • Division (/)
1 + 2       // equals 3
5 - 3       // equals 2
2 * 3       // equals 6
10.0 / 2.5  // equals 4.0

The addition operator is also supported for string concatenation:

"hello, " + "world"  // equals "hello, world"

Comparison Operators

LichenScript supports the following comparison operators:

  • Equal to (a == b)
  • Not equal to (a != b)
  • Greater than (a > b)
  • Less than (a < b)
  • Greater than or equal to (a >= b)
  • Less than or equal to (a <= b)

Each of the comparison operators returns a Bool value to indicate whether or not the statement is true:

1 == 1   // true because 1 is equal to 1
2 != 1   // true because 2 isn't equal to 1
2 > 1    // true because 2 is greater than 1
1 < 2    // true because 1 is less than 2
1 >= 1   // true because 1 is greater than or equal to 1
2 <= 1   // false because 2 isn't less than or equal to 1