A Beginner's to Master's Guide in Learning Lua

Date: October 1 2022

Summary: My notes on learning the Lua programming language

Keywords: #archive #lua #quick #start #programming

Bibliography

https://github.com/medwatt/Notes/blob/main/Lua/LuaQuickGuide.ipynb

Table of Contents

Reading Motivation

I wanted to learn Lua for no other reason than to program my own workflow in neovim. Also, Lua is cool and Just-in-Time compiled like Julia! Plus, it is used for game development so if ever this research thing doesn't work out, backup plan: become a game developer.

Comments

How to write comments within Lua!

-- This is my comment! 

--[[ 
	This
	is 
	a 
	multiline 
	comment! 
--]]

Variable Scope

Global Scope

All variables within lua are considered global by default. Moreover, each call or line within a lua script is run as a chunk.

Var = 10
print( "Global var:", Var )

Local Scope

To define a large chunk where variables are local in scope, one can create a local scope using a do-end block

do
	local Var = 20
	print( "Local Var:", Var )
end

Variable Assignments

A = A + 1 -- This works 
A += 1 -- This does not work 

B = 0 -- This works
C = 0 -- This works
B, C = 0, 0 -- This works
B = C = 0 -- This does not work

Variable Types

There are eight basic types within Lua:

• nil - represents absence of data

• boolean

• number - integer and float both exist as alternative subtypes of number

• string

• userdata

• function

• thread

• table

print( type("Hello") ) -- string 
print( type(10.4 * 3) ) -- number 
print( type({1, 2, 3}) ) -- table
print( type(print) ) -- function 
print( type(true) ) -- boolean 
print( type(nil) ) -- nil

NOTE: Arithmetic operations applied to an object of type string will not fail but instead Lua will attempt to convert that object to a number type. Vice-versa to this is that if a object of type number is used in a string operation, Lua will attempt to convert that object to a string.

Math Operators

A = 100
B = 2 

print( A + B ) -- Addition
print( A - B ) -- Subtraction 
print( A * B ) -- Multiplication
print( A ^ B ) -- Exponents 
print( A / B ) -- Division
print( A // B ) -- Floor
print( A % B ) -- Modulus
print( -A ) -- Negation

Relational Operators

A = 20
B = 4

print(A == B) -- false
print(A ~= B) -- true
print(A > B) -- true
print(A < B) -- false
print(A >= B) -- true
print(A <= B) -- false

Logical Operators

print(true and 10) -- evaluates to `10`
print(10 and true) -- evaluates `true`
print(false and 10) -- short circuits to `false`
print(false or 10) -- evaluates to `10`
print(nil and 10) -- evaluates to `nil`
print(nil or 10) -- evaluates to `10`
print(false and nil) -- evaluates to `false`
print(false and not(nil)) -- evaluates to `false`

How To Cite

Zelko, Jacob. A Beginner's to Master's Guide in Learning Lua. https://jacobzelko.com/10012022184345-learning-lua. October 1 2022.

References:

Discussion: