[slang-users] Is there a better way for two-type argument?

[Sebastian Gniazdowski <sgniazdowski@xxxxxxxxx>]

I'm utilizing ARRAY_2_VOIDP annotation to detect the actual type of an
argument and fill the remaining 2 (being the alternate type vars). The arg
map is below. I wonder if there is a better solution to allow passing
either string or integer to a SLang function?


% Allow a function (action()) to be called with either string or an integer
as its first
% argument and drop the last two. String is an action name (like
"EditFile"), while integer is the CK_ enum code.
#argmap(in, which=1, proxy=SLang_Array_Type) (void *ARRAY_2_VOIDP, char
*action_name, long action_code)
    {
        /* Called with string argument? */
        if (proxy->data_type == SLANG_STRING_TYPE) {
            $2 = *((char**)proxy->data);
            $3 = -1;
        } else {
            /* It's certain that no string will be passed. */
            $2 = NULL;
            /* Called with a long argument? */
            if (proxy->data_type == SLANG_LONG_TYPE)
                $3 = *((long*)proxy->data);
            /* Called with an integer argument? */
            else if (proxy->data_type == SLANG_INT_TYPE)
                $3 = *((int*)proxy->data);
            /* Unknown type passed as argument – signal/mark the error with
a special value. */
            else
                $3 = 0xbadc0de;
        }
        /*
         * The first parameter is only a placeholder of the void *
arbitrary type argument
         * on S-Lang side, it's unused on C side.
         */
        $1 = 0;
    }
#end

-- 
Sebastian Gniazdowski