floats as strings in Rust...

floatplus.rs

#[test]
fn rounding() {
   // trailing zeroes should be inserted, or rather
   // this dodgy floating point stuff should be rounded
   assert "3.141589999" == #fmt["%9.9f", 3.14159];
   assert "3.141589999" == float::to_str_common(3.14159, 9u, false);
   assert "3.141590000" == my_to_str_common(3.14159, 9u, false);            // FIXED

   assert "3.14158"     == float::to_str_common(3.14159, 5u, false);
   assert "3.14159"     == my_to_str_common(3.14159, 5u, false);            // FIXED
   
   // this truncation should be rounded
   assert "3.1415" == float::to_str(3.14159, 4u);
   assert "3.1416" == my_to_str_exact(3.14159, 4u);                         // FIXED
   assert "3"      == my_to_str_exact(3.14159, 0u);                         // FIXED
   assert "17"     == my_to_str_exact(16.9, 0u);                            // FIXED
   assert "7.0000" == my_to_str_exact(6.99999999, 4u);                      // FIXED

   // FIXME: epsilon calc should be adjusted and we should round these accordingly
   assert "3.14158999999999988261" == float::to_str_common(3.14159, 20u, false);
   assert "3.14158999999999988262" == my_to_str_exact(3.14159, 20u);        // STILL WEIRD
}