+ uint8_t *val;
+ int val_width = 1;
+
+ result = xmalloc (sizeof (*result));
+ result->intr = var;
+ n_vars = interaction_get_n_vars (var);
+ value_init (&result->val, val_width);
+ val = value_str_rw (&result->val, val_width);
+ val[0] = '\0';
+ result->f = 1.0;
+ for (i = 0; i < n_vars; i++)
+ {
+ member = interaction_get_member (var, i);
+
+ if (var_is_value_missing (member, vals[i], MV_ANY))
+ {
+ value_set_missing (&result->val, MAX_SHORT_STRING);
+ result->f = SYSMIS;
+ break;
+ }
+ else
+ {
+ if (var_is_alpha (var->members[i]))
+ {
+ int w = var_get_width (var->members[i]);
+ value_resize (result, val_width, val_width + w);
+ u8_strncat (val, value_str (vals[i], w), w);
+ val = value_str_rw (&result->val, val_width);
+ }
+ else if (var_is_numeric (var->members[i]))
+ {
+ result->f *= vals[i]->f;
+ }
+ }
+ }
+ if (interaction_get_n_alpha (var) == 0)