Declaring a Function

Part of the Fundamentals section of Coddy's Lua journey — lesson 50 of 90.

Functions are one of the most powerful tools in programming. Think of a function as a reusable block of code that performs a specific task. Instead of writing the same code multiple times, you can create a function once and use it whenever needed.

In Lua, you declare a function using the function keyword, followed by the function name, and ending with the end keyword:

function displayWelcomeMessage()
    print("Welcome to the game!")
end

This creates a function named displayWelcomeMessage that contains a single line of code. The parentheses () after the function name are required, even when the function doesn't take any inputs.

Challenge

Easy

Create a game notification system by declaring a function that displays a welcome message to players. Declare a function named showGameWelcome that contains a single print() statement to output "Welcome to Adventure Quest!". Remember that declaring the function creates it but doesn't execute the code inside - the function is ready to be called later.

Cheat sheet

Functions are reusable blocks of code that perform specific tasks. In Lua, declare a function using the function keyword and end with end:

function displayWelcomeMessage()
    print("Welcome to the game!")
end

The parentheses () after the function name are required, even when the function doesn't take any inputs. Declaring a function creates it but doesn't execute the code inside.

Try it yourself

-- TODO: Write your code here to declare the showGameWelcome function

-- Call the function to display the welcome message
showGameWelcome()

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Fundamentals

1Introduction

The Language Hello World!Comments

4Operators 2 Relational & Logic

Equality Operators Relational Operators The 'and' Operator The 'or' Operator The 'not' Operator Short-Circuit Evaluation Truthy and Falsy Values Recap - Simple Logic

7Basic Conditional Logic

The if-then Statement The if-then-else Statement The elseif Statement Recap - Treasure Chest

10Tables Part 1: List-Style

What is a Table?Creating a Table Accessing Elements by Index Modifying Elements by Index The Length Operator '#'table.insert()table.remove()Recap - Manage Party Members

13Project: Simple Potion Shop

Project Setup Adding a Potion

Displaying the Inventory

Calculating Total Stock Value

Finding a Specific Potion

Selling a Potion

3Operators 1 Arithmetic & Conc

Arithmetic Operators Modulo Operator Exponentiation Operator String Concatenation Operator Precedence Recap - Simple Calculations

6Project: Character Stats Disp

Welcome Message Declare Character Stats

Display Basic Stats

Add a Boolean Flag

Final Summary

9Functions Basics

Declaring a FunctionCalling a Function Functions with Parameters Functions with Multiple Params The 'return' Statement Recap - Area Calculator

12Loops Basics

The while Loop The repeat-until Loop The Numeric for Loop for Loop with a Step The 'break' Statement Recap - Countdown

15Final Challenges

Recap - Player Turn Recap - Simple Database Recap - Sum of Even Numbers