Functions and Procedures

Functions allow you to organize code into reusable blocks that can be called from different parts of your program. They’re essential for writing clean, maintainable code.

Basic Function

A function that returns a value:

function hello takes in nothing
    return "world"

Or simply:

function hello
    return "world"

Functions with Parameters

Single Parameter

function square takes in number
    return number * number

result = square(5)  // Returns 25

Multiple Parameters

function add takes in num1 and num2
    return num1 + num2

sum = add(10, 20)  // Returns 30

Three or More Parameters

function calculateVolume takes in length and width and height
    volume = length * width * height
    return volume

volume = calculateVolume(5, 3, 2)  // Returns 30

Calling Functions

Standard Syntax

result = functionName(arg1, arg2)

Natural Language Syntax

result = run functionName with arg1 and arg2

Example

function multiply takes in a and b
    return a * b

// Both ways work
result1 = multiply(5, 3)
result2 = run multiply with 5 and 3

Procedures (No Return Value)

Functions that perform actions but don’t return a value:

function printGreeting takes in name {
    output "Hello, {name}!"
    output "Welcome to the program!"
}

// Call the procedure
printGreeting("Alice")
/* Output:
   Hello, Alice!
   Welcome to the program! */

Return Statements

Functions can return values using the return keyword:

function isAdult takes in age {
    if age >= 18
        return true
    return false
}

function getGrade takes in score
    if score >= 90
        return "A"
    else if score >= 80
        return "B"
    else if score >= 70
        return "C"
    else if score >= 60
        return "D"
    return "F"

Simple Example

function calculateArea takes in width and height
    return width * height

function calculatePerimeter takes in width and height
    return 2 * (width + height)

// Usage
w = 10
h = 5
output "Area: {calculateArea(w, h)}"
output "Perimeter: {calculatePerimeter(w, h)}"