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599 :: Lua and LuaL_Reg

• dirkwillem (orginal) [2014-10-22T18:39:52+02:00] view original

  Hello

  I've been playing around with Nim a bit, and I like what I see. Now I'm trying to port my C++ Lua framework to it, but I've got a problem. The part of C++ Code I can't get to work in Nimrod is this:

  luaL_Reg led[] = {
      {"__index", L_LED_Get},
      {"__newindex", L_LED_Set},
      {NULL, NULL}
  };
  luaL_newmetatable(L, MT_LED);
  luaL_setfuncs(L, led, 0);
  Run

  In C, the declaration luaL_setfuncs is this

  lua_setfuncs(lua_State* L, luaL_Reg* L2, nup: int);
  Run

  In Nimrod, the declaration of setfuncs is this:

  proc setfuncs*(L: PState; L2: ptr luaL_Reg; nup: cint) {.iluaL.}
  Run

  and the code I have now is this:

  let led:array[2, LuaL_Reg] = [(cstring("__index"), TCFunction(Index)),(cstring("__newindex"), TCFunction(Index))]
  state.SetFuncs(led, 0) #doesn't compile
  Run

  So how do I transform this array in to a "C-Style" pointer array?

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• will (orginal) [2014-10-22T18:56:38+02:00] view original

  I may be wrong, but I think you want to take the addr of the 0th element in the array:

  
  state.SetFuncs(led[0].addr, 0)
  Run

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• dirkwillem (orginal) [2014-10-22T18:58:44+02:00] view original

  That won't compile, it gives this error:

  main.nim(20, 24) Error: expression has no address
  Run

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• will (orginal) [2014-10-22T18:59:53+02:00] view original

  change

  "let led" to "var led":

  
  var led:array[2, LuaL_Reg] = [(cstring("__index"), TCFunction(Index)),(cstring("__newindex"), TCFunction(Index))]
  state.SetFuncs(led[0].addr, 0)
  Run

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• mason_mcgill (orginal) [2014-10-22T19:03:31+02:00] view original

  Try just changing :

  state.SetFuncs(led, 0)

  to:

  state.SetFuncs(addr led, 0)

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• mason_mcgill (orginal) [2014-10-22T19:07:02+02:00] view original

  Though will is right that led should be a variable (otherwise taking its address would be unsafe).

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