new `luaL_weakregistry' function

This commit is contained in:
Roberto Ierusalimschy 2002-06-25 16:15:21 -03:00
parent fdfd5b44ee
commit 89b102bd1d
2 changed files with 24 additions and 3 deletions

View File

@ -1,5 +1,5 @@
/*
** $Id: lauxlib.c,v 1.74 2002/06/13 13:44:50 roberto Exp roberto $
** $Id: lauxlib.c,v 1.75 2002/06/18 15:19:27 roberto Exp roberto $
** Auxiliary functions for building Lua libraries
** See Copyright Notice in lua.h
*/
@ -143,7 +143,7 @@ LUALIB_API int luaL_callmeta (lua_State *L, int obj, const char *event) {
return 0;
}
lua_pushvalue(L, obj);
lua_upcall(L, 1, 1);
lua_call(L, 1, 1);
return 1;
}
@ -299,6 +299,25 @@ LUALIB_API void luaL_unref (lua_State *L, int t, int ref) {
}
LUALIB_API void luaL_weakregistry (lua_State *L) {
static const char dummy = '\0'; /* index for a weak table in registry */
lua_pushudataval(L, (void *)&dummy); /* push index */
lua_rawget(L, LUA_REGISTRYINDEX); /* get value */
if (!lua_isnil(L, -1)) return; /* weak table already created? */
/* else must create a weak table */
lua_pop(L, 1); /* remove previous nil */
lua_newtable(L); /* new table `w' */
lua_pushvalue(L, -1);
lua_setmetatable(L, -2); /* setmetatable(w, w) */
lua_pushliteral(L, "__mode");
lua_pushliteral(L, "kv");
lua_rawset(L, -3); /* metatable(w).__mode = "kv" */
lua_pushudataval(L, (void *)&dummy); /* push index */
lua_pushvalue(L, -2); /* push value */
lua_rawset(L, LUA_REGISTRYINDEX); /* store new weak table into registry */
}
/*
** {======================================================
** Load functions

View File

@ -1,5 +1,5 @@
/*
** $Id: lauxlib.h,v 1.48 2002/06/03 20:11:41 roberto Exp roberto $
** $Id: lauxlib.h,v 1.49 2002/06/18 15:19:27 roberto Exp roberto $
** Auxiliary functions for building Lua libraries
** See Copyright Notice in lua.h
*/
@ -49,6 +49,8 @@ LUALIB_API int luaL_error (lua_State *L, const char *fmt, ...);
LUALIB_API int luaL_findstring (const char *name,
const char *const list[]);
LUALIB_API void luaL_weakregistry (lua_State *L);
LUALIB_API int luaL_ref (lua_State *L, int t);
LUALIB_API void luaL_unref (lua_State *L, int t, int ref);