modify mrb_to_str() in order to display big float number

src/numeric.c

@@ -187,7 +187,8 @@ mrb_flo_to_str(mrb_state *mrb, mrb_value flo, int max_digit)
       }
 
       if (exp >= 100) {
-        mrb_raise(mrb, E_RANGE_ERROR, "Too large exponent.");
+        *(c++) = '0' + exp / 100;
+        exp -= exp / 100 * 100;
       }
 
       *(c++) = '0' + exp / 10;