Lua Course Lecture Notes

Introduction to Lua

• Lua is a procedural programming language.
• It is used to develop software, work with machine learning, and create games (from text games to VR games).
• Popular for game development; often paired with C/C++.

Course Overview

• Difficulty: Relatively easy; no prior programming knowledge required.
• Duration: About 4-5 hours; can be completed in about a week with determination.
• Execution Speed: Fast; suitable for games.
• Types: Procedural and object-oriented.

Projects Developed with Lua

• Adobe Photoshop Lightroom
• Apache HTTP Server
• Roblox games
• Angry Birds
• World of Warcraft

Getting Started

Installation of Lua

• To install Lua on Linux (Arch): sudo pacman -S lua
• For Windows/Mac: Download from the Lua website.

Creating Your First Lua File

• Ensure the file ends with .lua, not .txt (Windows users).
• Use a code editor (e.g., VS Code) to write code.

Printing Text

• Use print() function to display text.
• Example: print("Hello World")

Comments

• Single line comment: -- Comment
• Multi-line comment: --[[ Comment ]]

Basic Types in Lua

• Nil: Represents no value.
• Number: e.g., 1, 0.1, 44.5.
• String: Text enclosed in quotes.
• Boolean: True/False.
• Tables: Complex data structures (arrays, dictionaries).

Variables

• Create a variable using local keyword.
• Example: local a = 10
• Variables can change values over time.

Basic I/O

• Use terminal for I/O operations.

Mathematical Operations

• Basic arithmetic: +, -, *, /.
• Order of operations: parentheses, exponents, multiplication/division, addition/subtraction.
• Use math library for more complex operations.*

Strings in Lua

• Strings can be concatenated with .. operator.
• Escape characters: e.g., backslash \
• String length: #string

Control Structures

If Statements

• Syntax: if condition then ... end
• Use comparison operators (>, <, ==).

Loops

• For Loop: for i = 1, 10 do ... end
• While Loop: while condition do ... end

Functions

• Declare functions with function keyword.
• Can return values using return keyword.
• Functions can have parameters.

OOP in Lua

• Simulate OOP with tables and functions.
• Create objects using functions returning tables.
• Inheritance can be simulated with metatables.

Metatables

• Use metatables to define custom behaviors for tables (e.g., addition).
• Define meta methods like __add, __sub, etc.

Modules in Lua

• Define reusable code in separate files (modules).
• Use require to import a module.

OS Module

• Interact with the operating system.
• Get environment variables, execute commands, and manipulate files.

Conclusion

• Lua is versatile and great for game development.
• Explore libraries and further resources for learning Lua.