- Corona SDK Mobile Game Development：Beginner's Guide
- Michelle M. Fernandez
- 231字
- 2021-08-06 19:59:45
Types of values
Lua is a dynamically typed language. There is no defined type in the language. Each value carries its own type.
As you have noticed, values can be stored in variables. They can be manipulated to give a value of any type. This also allows you to pass arguments to other functions and return as results.
The basic types of values that you'll deal with are the following:
nil—It is the only type whose value isnil. Any uninitialized variable hasnilas its value. Like global variables, it isnilby default and can be assignednilto delete it.Boolean—TheBooleantype has two values,falseandtrue. You will notice that conditional expressions considerfalseandnilas false and anything else as true.Numbers—Represents real (double-precision floating-point) numbers.String—AStringis a sequence of characters. 8-bit characters and embedded zeros are allowed.Tables—A data structure in Lua. It is implemented by an associative array, which is an array that can be indexed not only with numbers, but also with strings or any other value, exceptnil. (We will discuss more about this in the section Tables later in this chapter).Functions—Known as first-class values of Lua. Typically, functions can be stored in variables, passed as arguments to other functions and returned as results.