global to dimTwoD(int xSize, int ySize) into (array of array of string aa)
/* Return a two-dimensional array of given size initialized to zero.
 * Hopefully at some point the language will make this easier. */
    {
    array[ySize] of array of string res;
    aa = res;
    for (int i=0; i<ySize; i += 1)
        {
	array [xSize] of string a;
	aa[i] = a;
	for (int j=0; j<xSize; j += 1)
	    a[j] = " ";
	}
    }