FW: lua_isnumber modifying variables

[Mike Elson <Mike.Elson@...>]

I'm using lua 4.01, and trying to pass string of numerical digits from a lua
script to a C++ application, _without_ converting it to a number on route.

Heres some code that illustrates the problem:

int main(void)
{
    lua_State* state = lua_open(0);
    lua_dostring(state,
"one=\"1111111011111111000111110000000000000000111111001111111100111111\"");
    lua_getglobal(state, "one");
    cout << "Isnumber returns " << lua_isnumber(state, -1) << endl;
    cout << "Isstring returns " << lua_isstring(state, -1) << endl;
    cout << "Read 'one', it is '" << lua_tostring(state, -1) << "'\n";
    lua_close(state);
    return 0;
}

and the result:

Isnumber returns 1
Isstring returns 1
Read 'one', it is '1.111111011111111e+63'

It has changed the string "one" into a floating point number.
If I remove the call to "lua_isnumber" the result is:

Isstring returns 1
Read 'one', it is
'1111111011111111000111110000000000000000111111001111111100111111'

Which is the result I'm after.

I can work around this by calling lua_type instead of lua_isnumber, but it
doesn't seem right that lua_isnumber should modify the variable it is
testing - is this behaviour correct?

Mike.