A Boolean has one of two possible values: true or false. Boolean (logical) operators (and, or, not) take Boolean inputs and make another Boolean value. Comparison operators on other types (numbers, strings) create Boolean values.

These blocks represent the true and false Boolean values, which can plug into anyplace a Boolean value is expected:


The next three blocks represent the three Boolean (logic) operators:

true && false;
true || false;

The next six blocks represent comparison operators that yield a Boolean value. Most comparisons you will do involve numbers:

42 == 0;
42 != 0;
42 < 0;
42 > 0;
42 <= 0;
42 >= 0;

Boolean values and operators are often used with an if or while statement to determine which code will execute next. For example:

Functions that return a Boolean

Some functions return a Boolean value, which you can store in a Boolean variable. For example, the following code gets the on/off state of point (1, 2) and stores this in the Boolean variable named on. Then the code clears the screen if on is true:

Boolean operators

Boolean operators take Boolean inputs and evaluate to a Boolean output:

Conjunction: A and B

A and B evaluates to true if-and-only-if both A and B are true:

false && false == false;
false && true == false;
true && false == false;
true && true == true;

Disjunction: A or B

A or B evaluates to true if-and-only-if either A is true or B is true:

false || false == false;
false || true == true;
true || false == true;
true || true == true;

Negation: not A

not A evaluates to the opposite (negation) of A:

!false == true;
!true == false;

Example: AND operator

This example turns on LED 3 , 3, if LEDs 1 , 1 and 2 , 2 are both on:

if (led.point(1,1) && led.point(2,2)) {

Example: Comparisons of numbers and strings

When you compare two Numbers, you get a Boolean value, such as the comparison x < 5 in the code below:

input.onButtonPressed(Button.A, () => {
    let x = Math.random(5)
    if(x < 5) {
    } else { 

See the documentation on Numbers for more information on comparing two Numbers.