https://github.com/agneay/lua-cheatsheet
A simple cheat sheet for lua programming language
https://github.com/agneay/lua-cheatsheet
cheatsheet lua lua-cheatsheet
Last synced: 10 months ago
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A simple cheat sheet for lua programming language
- Host: GitHub
- URL: https://github.com/agneay/lua-cheatsheet
- Owner: agneay
- License: mit
- Created: 2024-04-09T13:26:00.000Z (about 2 years ago)
- Default Branch: main
- Last Pushed: 2024-04-13T08:10:53.000Z (almost 2 years ago)
- Last Synced: 2025-06-25T02:07:58.090Z (10 months ago)
- Topics: cheatsheet, lua, lua-cheatsheet
- Homepage:
- Size: 8.79 KB
- Stars: 0
- Watchers: 1
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# Welcome to Lua-Cheatsheet
---
---
## Comments :
---
Comments in lua are of two types:
- single line comment
- multi line comment
### single line comment:
A single line comment in lua is given by adding `--` to the begining of the line
For example:
```lua
-- This is a comment
```
It is not necessary to leave a space after `--` to the make a comment
For example:
```lua
--This is also a comment
```
Lua also does not restrict the number of comments possible for example
```lua
-- this is comment 1
-- this is comment 2
-- this is comment 3
```
### multi line comment :
A multiline comment is lua begins with `--[[` and ends with `]]`
For example:
```lua
--[[
This
is
a
multiline
comment
]]
```
> Make sure there is no space between `--` and `[[` in the start of the multiline comment as doing so will cause `Error`
> NOTE: Comments can be place wherever we want for example they can be placed after a meaningful statements
>
> For example:
>
> ```lua
> print("Hello World!") -- This statement will be ignored
> ```
## Printing stuffs onto screen:
In lua we can print
- texts
- variables
### printing texts onto screen:
To print text onto screen we need to simply use the print statement in the following format is `print()`
For example:
```lua
print("Hello World!")
```
> Note: A string will always be enclosed be quotation marks
We are also not limited to the number of print statements we can have
For example:
```lua
print("Hello World!")
```
> Note: A string will always be enclosed be quotation marks
We are also not limited to the number of print statements we can have
For example:
```lua
print("Hello World !")
print("My name is AGNEAY B NAIR")
```
To print multiple text using the same print statement we can use of the below given format
Format:
```lua
print("HELLO WORLD","I LOVE LUA")
```
the above print statement will display the two strings together by seperating them by a `tab` space
inorder to concatenate two strings using the `print` statement in lua use `..` instead of `, ` in the print statement
For example:
```lua
print("Hello world!".." I love lua !")
```
will concatenate both the strings
## Variables and data types:
- The undefined data types: The `nil` data type is undefined and empty
- The number data type: `number`
- `string` data type : all characters enclosed within quotes
- `boolean` data type: `true` and `false`
- `tables` data type: The equivalent of array or list present in different programming languages
## To create a local variable
```lua
local name
```
here `name` is the variable name
lua always explicitly places the nil data type to the variable . Hard to believe ? Let's try it out
```lua
local name
print(name)
```
This would return nil as the variable name stores nil
we can also implicitly give `name` the value nil as
For example:
```lua
local name = nil
print(name)
```
It is not necessary to define the value in the same line as that in which we define the variable
```lua
local name
name = nil
print(name)
```
we can also use print statement to display the value of expressions
For example:
```lua
local x = 3
print(x+8)
```
## To define a global variable
```lua
GlobalVar = 3
```
Here the variable `GlobalVar` has the value 3 and is globally defined and can be imported in other lua files
inorder to define a global variable to lua more spefically to lua we could write
```lua
_G.GloablVar = 3
```
Here the prefix _G. will make it clear to lua that we intend to create a global variable and not a local variable
> NOTE: we need not use _G. always it is completly optional
## To define multiple local variable at the same time
```lua
local name,age,gender
```
now we have defined three variables at the same time
we could also give them values as we define them as
```lua
local namea,nameb,namec = "ram","lak","shah"
```
here we have created three variable having same data type , but this is not a necessesity ie we can define variables having different data type in the same line
```lua
local name,age,gender = "AGNEAY",18,"MALE"
```
## Getting the length of the string
we can get the length of any string in lua with the help of `#`
For example:
```lua
local x = "AGNEAY B NAIR"
print(#x)
```
The above code will return the length of string, we can also do it this way
```lua
local x = #"AGNEAY B NAIR"
print(x)
```
## To check the type of a given data type
we can simply use `type()` function provided by lua
For example:
```lua
local x = "AGNEAY B NAIR"
local y = 13
local z = true
print(type(x),type(y),type(z))
```
## To convert a number to string:
we can use the `tostring()` function provided by lua
```lua
local x = 18
print(type(x))
local y = tostring(x)
print(type(y)
```
## Escape sequence
| Escape sequence | meaning |
|:---------------:|:-----------------:|
| \n | newline character |
| \t | tab space |
| \\\ | \ |
## String functions
Some string functions are
```lua
local name = "Agneay"
print(String.upper(name))
print(String.lower(name))
print(String.len(name))
```
The String.upper() function will convert all the string letters to upper case and so is the case with String.lower() with the only difference being it will translate the string in lower case and String.len() will return the length of the string