hi,
here is a snippet that i use in one of my programs.
if(lua_istable(L,-2)) {
lua_settop(L,-2);
int index=-2;
lua_pushnil(L);
int key; double value;
while(lua_next(L,index) != 0) {
if(!lua_isnumber(L,-2) ||
!lua_isnumber(L,-1)) E("[ERR] C:set_lib_data - invalid key,value
pair\n")
else {
key =
(int)lua_tonumber(L,-2); value = lua_tonumber(L,-1);
M("[INFO] key: " <<
key << " value: " << value << endl)
}
lua_pop(L,1);
}
lua_pushnumber(L,1);
}else { E("[ERR] C:set_lib_data - invalid
argument 2\n") }
hope this helps.
-Abhinav
On Wed, Apr 9, 2008 at 7:01 AM, Eugen-Andrei Gavriloaie
<shiretu@gmail.com> wrote:
Hi,
It might sound stupid, but it seems that I can't find a way to
iterate
through a table in c++. Suppose we have a table pushed onto the
stack (lua
calls a c++ function and passes all the parameters using a table:
key/value
pairs). How do I iterate on that table (present on the top of
stack) in c++?
I need both elements (key and value).
Please don't make fun of me now because I think I'll try to scratch
with my
left on the right side of my head .... :)
One approach would be to globalize the table from the stack by
giving it a
name using lua_setglobal and after that evaluate a generated lua
script like
this:
for k,v in pairs(_some_random_name) do
call_another_cpp_function_that_handles_only_one_row_in_the_table(k,v)
end
evaluation is made using lua_loadstring()/lua_pcall()
After this, we can use lua_setglobal again to set
`_some_random_name` to
nil and make the table available for GC.
But this is a huuuuge implementation overhead IMHO, because you
must keep a
state in c++ outside the function
call_another_cpp_function_that_handles_only_one_row_in_the_table
(store the
key/value pair (now present on the stack like 2 distinct elements,
easy to
pick up) into a more
