Dart Essentials: Arithmetic and Logical Operations

Are you ready to start, coder? Today, we're exploring the fundamentals of Dart, focusing on arithmetic and logical operations on basic types. These concepts are essential for data processing and decision-making in the development of your applications.

From our previous discussions, Dart's basic types are int for integer numbers, double for floating point numbers, bool for true/false values, and String for text. Both int and double have constraints on their numerical range. We will explore these constraints further when we describe overflow later in this session.

Arithmetic operations, such as addition (+), subtraction (-), multiplication (*), division (/), and modulus (remainder of a division, symbolized by %), can be performed on numerical types. For instance:

int a = 10;
int b = 2;
int c = 3;

print(a + b); // Outputs: 12
print(a - b); // Outputs: 8
print(a * b); // Outputs: 20
print(a / b); // Outputs: 5.0
print(a % b); // Outputs: 0
print(a % c); // Outputs: 1
print(b % c); // Outputs: 2
print(c % a); // Outputs: 3

Dart supports the alteration of order using parentheses and provides the modulus (%) operation, which is useful for determining if numbers are even or odd.

Logical operators — && (AND), || (OR), ! (NOT) — function as decision-makers in Dart and evaluate to bool values — true or false. Here's how you can use them with two bool values:

print(true && true); // true
print(true && false); // false
print(false && true); // false
print(false && false); // false

print(true || true); // true
print(true || false); // true
print(false || true); // true
print(false || false); // false

print(!true); // false
print(!false); // true

In this context, && produces true if both boolean values are true. || outputs true if either value is true, and ! flips the boolean value.

The primary application of logical operations is with variables. Here's a simple illustration of how you can use them for decision-making:

int speed = 60;
int minSpeed = 30;
int maxSpeed = 70;
// Verify if the speed is within the expected range.
print(speed > minSpeed && speed < maxSpeed); // Prints: true