Lua tutorial-Basics

1. Keyword

And	Break	Do	Else	Elseif
End	False	For	Function	If
In	Local	Nil	Not	Or
Repeat	Return	Then	True	Until	While

2. Data Type

How can we determine the type of a variable? You can use the type () function to check. Lua supports the following types:

Nil	Null Value. All unused variables are nil. Nil is both a value and a type.
Boolean	Boolean value. There are only two valid values: true and false.
Number	Numeric value. In Lua, the value is equivalent to double in C.
String	String. If you want to, the string can contain the "\ 0" character (which is different from the C language that always ends with "\ 0)
Table	Link Table type. This type is powerful. For more information, see the following section.
Function	Function type. Do not doubt that a function is also a type. That is to say, all functions are a variable.
Userdata	Well, this type is used to deal with Lua's host. Generally, the host is written in C and C ++. In this case, userdata can be any data type of the host, usually including struct and pointer.
Thread	Thread type. There is no real thread in Lua. In Lua, a function can be divided into several parts for running. If you are interested, you can go to Lua's documents. Now let's look back at it. I don't think it's a thread type. Instead, the iterator function is used for traversal. For example: Function range (N) Local I = 0 While (I <n) Do Coroutine. Yield (I) I = I + 1 End End Unfortunately, you need the coroutine. Resume function to continue running. Please advise.