mirror of
https://github.com/quizhizhe/LiteLoaderBDS-1.16.40.git
synced 2025-06-07 20:28:10 +00:00
125 lines
2.5 KiB
Markdown
125 lines
2.5 KiB
Markdown
# Lua语言
|
||
|
||
ScriptX和Lua语言类型对照表
|
||
|
||
| Lua | ScriptX |
|
||
| :--: | :--: |
|
||
| nil | Null |
|
||
| table | Object |
|
||
| table | Array |
|
||
| string | String |
|
||
| number | Number |
|
||
| boolean | Boolean |
|
||
| function | Function |
|
||
|
||
## 1-based or 0-based?
|
||
Lua语言使用1作为基数，但是C++语言是用0作为基数。因此在ScriptX中，对于数据等的操作，仍然使用0-based逻辑。
|
||
|
||
比如:
|
||
```c++
|
||
Local<Array> arr;
|
||
arr.set(0, "hello");
|
||
|
||
// lua
|
||
arr[1] == "hello";
|
||
```
|
||
|
||
## Lua函数多返回值
|
||
|
||
Lua函数支持多返回值，但是ScriptX的API只支持返回 `Local<Value>`。
|
||
|
||
当Lua函数返回多个值的时候，ScriptX会把返回值用Array包起来。
|
||
|
||
## ByteBuffer
|
||
|
||
Lua语言没有ByteBuffer相关的API，因此ScriptX通过 binding API提供了一套实现。
|
||
|
||
同时在LuaEngine的构造函数里，使用者也可以传入自己的delegate实现ByteBuffer相关API
|
||
|
||
## instanceOf
|
||
|
||
Lua语言没有内建的 `instanceof` 操作符，为了实现相应能力，ScriptX会在Lua全局增加一个`ScriptX`工具类。
|
||
|
||
`ScriptX.isInstanceOf(instance, Class)`
|
||
|
||
```c++
|
||
// C++
|
||
class InstanceOfTest : public script::ScriptClass {
|
||
public:
|
||
using ScriptClass::ScriptClass;
|
||
};
|
||
|
||
auto instanceOfTestDefine =
|
||
defineClass<InstanceOfTest>("InstanceOfTest")
|
||
.constructor()
|
||
.build();
|
||
```
|
||
``` lua
|
||
# lua
|
||
local ins = InstanceOfTest();
|
||
ScriptX.isInstanceOf(ins, InstanceOfTest) == true;
|
||
```
|
||
|
||
## 绑定类的MetaData
|
||
|
||
由于Lua没有标准的OO，对于一个ClassDefine，ScriptX会在lua中定义如下声明：
|
||
|
||
```lua
|
||
Class = {}
|
||
|
||
local staticMeta = {
|
||
// constructor call
|
||
__call = function()
|
||
local ins = {};
|
||
setmetatable(inx, instanceMeta);
|
||
return ins
|
||
end
|
||
}
|
||
|
||
for staticFunc do
|
||
Class[staticFunc.name] = function() ... end
|
||
end
|
||
|
||
setmetatable(Class, staticMeta)
|
||
|
||
local instanceMeta = {
|
||
__index = function()
|
||
1. find from `ClassDefine.instanceProperty`
|
||
2. find from `ClassDefine.instanceFunction`
|
||
3. return nil
|
||
end
|
||
|
||
__newindex = function()
|
||
1. find from `ClassDefine.instanceProperty`
|
||
2. raw set to table
|
||
|
||
__gc = function()
|
||
1. delete this
|
||
end
|
||
|
||
instanceFunction = {...}
|
||
|
||
}
|
||
|
||
ScriptX.getInstanceMeta(Class) == instanceMeta;
|
||
```
|
||
|
||
比如，要扩展一个绑定的类，可以如下：
|
||
|
||
```lua
|
||
local meta = ScriptX.getInstanceMeta(Class)
|
||
function meta:__add() print(self, "add") end
|
||
function meta.instanceFunction:hello()
|
||
print(self, "hello")
|
||
end
|
||
|
||
// test
|
||
local ext = Class()
|
||
x = ext + ext
|
||
ext:hello();
|
||
|
||
// output
|
||
table: 0x7fc873c18ed0 add
|
||
table: 0x7fc873c18ed0 hello
|
||
```
|