??Lua

1
??Lua

• ????????????

2
???Lua

• Lua?????????,?1994?,??????????????????????,Lua??
  ????????? ???
• ???????? PHP?Perl?JavaScript ???,Lua?????????
  ????,Lua????????????????? ???? ??
• Lua????????
• ??? ?????? ?????????????
• ??? ?API?????????? ????

3
????????

• Lua??????????,?????????????Lua??????????????????,?
  ??? Java?Python ??????????(?????????????),?????,??
  ???????
• Lua??????,??????,?? ???????(???????
  )???????,???????????????????,???????????
• Lua????????C/C,Java,.NET,???????PHP,Ruby??

4
Lua???????

• Lua??????,???????????

• ?????????,Lua??????

????
Lua
????
Lua
5
Lua??????????

• Lua????????,????????? ???????????,???????????
  ?????????????

6
????

• 1.??????Lua??????
• 2.????????Lua??(??),????,???Lua????,?????
• 3.??Lua??????????Lua??(?????????????????)?
• 4.?????Lua???

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Lua??????????

• ?????????,?Lua???????????????
• ???????????Lua??????
• ?????????????Lua????
• Lua???????????

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???????demo1.c

• include ltlua.hgt //Lua?????
• include ltlualib.hgt //Lua???
• include ltlauxlib.hgt //Lua????
• char code "for i0, 5 do print(\'Hello,
  world!\') end"
• int main()
• lua_State s luaL_newstate() //???????
• luaL_openlibs(s) //??Lua???
• luaL_dostring(s, code) //??????????
• lua_close(s) //?????
• return 0

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?????

• ??gcc o demo1 demo1.c llua
• ??./demo1
• ????
• Hello, world!
• Hello, wordl!
• Hello, world!
• Hello, world!
• Hello, world!
• ??Lua????????,???API,????????Lua???,??????????????

10
??????

• ???????Lua?????,?????Lua???????????????
• ????????????,Lua?????????,??????????????,??????Lua
  API?????,?Lua?????????????
• ????????????????Lua??,???Lua????????,????SQL????,
  ?????????????

11
???????

• ??f (a, b, c)

c
b
??lua_call(s, 3, 1)?
a
f
f(a, b, c)


?????? ????????
?????????? ??????
12
???????

• Lua??????????,Lua API????????,????????,?????????,?
  ???????????,??????????????
• ??????????Lua?????,????????????,???????,??????????
  ??????lua_register???Lua???(????????Lua????????),?
  ???Lua??????
• ????????Lua????,????????,????lua_call,???Lua??????

13
Lua??????

• ?Lua???????N???,???? 1 N ???????,???? -1 -N
  ???????,?????????
• ???????????????Lua????,??????????,?????????????

-1
lt????gt
6
-2
lt??gt
5
-3
1, "ab", nil
4
-4
"hello"
3
-5
false
2
-6
123
1
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?????????demo2.c

• include ltlua.hgt
• include ltlualib.hgt
• include ltlauxlib.hgt
• int divide(lua_State s) //?Lua?????????
• double a lua_tonumber(s, -2) //???????
• double b lua_tonumber(s, -1) //???????
• int quot (int)a / (int)b
• int rem (int)a (int)b
• lua_pushnumber(s, quot) //?????????
• lua_pushnumber(s, rem) //?????????
• return 2 //????????

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?demo2.c?demo2.lua

• int main()
• lua_State s luaL_newstate()
• luaL_openlibs(s)
• lua_register(s, "div, divide) //????????
• luaL_dofile(s, "demo2.lua") //?????????
• lua_close(s)
• return 0
• demo2.lua
• a 13
• b 5
• q, r div(a, b) //????
• print(q, r)

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???????

• ??
• 2 3
• ?????,??Lua??????????????int f(lua_State
  s),??????????,????????????????????Lua???????,???
  ???????????,Lua????????????,??????????
• ??,?Lua?????????????,??Lua???????,???????????????

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????????demo3.c

• include ltlua.hgt
• include ltlualib.hgt
• include ltlauxlib.hgt
• int main()
• lua_State s luaL_newstate()
• luaL_openlibs(s)
• luaL_dofile(s, "demo3.lua")
• lua_getglobal(s, "show") //?Lua??????
• lua_pushstring(s, "It is from C") //??????
• lua_call(s, 1, 1) //??Lua??

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?demo3.c?demo3.lua

• const char result lua_tostring(s,
  -1) //????????
• printf("C has got s\n", result)
• lua_pop(1) //?????
• lua_close(s)
• return 0
• demo2.lua
• show function(m)
• print('Lua has got ' .. m)
• return 'It is from Lua'
• end

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???????

• ??
• Lua has got It is from C
• C has got It is from Lua
• ??,???????????????Lua?????,?Lua???????????????????
  ,???Lua??????????????,????????????Lua????

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Lua????

• ????,???????,?????????????????????
• ???????,??????,?????????,???????
• ??????????????????
• ???????????,??????????
• ???????????????

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????/????

• ??a 3 x, y, z 12, 'Hello', true
• ????
• ??? nil nil
• ?? number 123 3.14159 1.6e-9
• ?? - / (??) -(?)
• ?? boolean true false
• ??or and not
• ??? string 'www.feedsky.com' "?????"
• ??..(??) (??)
• ???????
• gt lt gt lt

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?

• Lua???(table)?????????????
• t 1234, nil, 'something', true, 'nested',
  1.414
• table??????,???-?????,?????,?????1?????????????
• rec name ????', favorite '????',
  32 true
• ??????
• rec.name rec'favorite' rec8-3
• ?????,??????????????????????????

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??

• ?????Lua?????,???????,???????????,??????????????
• r2p function(x, y)
• abs math.sqrt((x x) (y y))
• arg math.atan2(x, y)
• return abs, arg
• end
• ????
• rho, theta r2p(3, 4)
• ????????,???????????

24
???????

• ??(coroutine)???????????????,???CPU??????(??)?????
  
• ??????(yield)?I/O???????
• ??????(yield)?I/O(?????)??
• ??,?????????????????,??????????,????????,???????
  ????????
• ??????????,?????????????????????????????????,???
  ??????????????????????,???OS??????
• ???????????????????,?????????????,??????????

25
??

• Lua????????????????????,????????????
• ??????Lua,?????????????????????
• ???????????,???????,Lua?????????????????

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http//lych.yo2.cn?????

• ??,???????blog