Simplify std::num::Primitive trait definition

This removes the `Primitive::{bits, bytes, is_signed}` methods and removes the operator trait constraints, for the reasons outlined below:

- The `Primitive::{bits, bytes}` associated functions were originally added to reflect the existing `BITS` and `BYTES` statics included in the numeric modules. These statics are only exist as a workaround for Rust's lack of CTFE, and should probably be deprecated in the future in favor of using the `std::mem::size_of` function (see #11621).

- `Primitive::is_signed` seems to be of little utility and does not seem to be used anywhere in the Rust compiler or libraries. It is also rather ugly to call due to the `Option<Self>` workaround for #8888.

- The operator trait constraints are already covered by the `Num` trait.

1 files changed, 1 insertions, 17 deletions

diff --git a/src/libstd/num/int_macros.rs b/src/libstd/num/int_macros.rs
index add0991f7af..80bc24e2d62 100644
--- a/src/libstd/num/int_macros.rs
+++ b/src/libstd/num/int_macros.rs
@@ -361,16 +361,7 @@ impl Bounded for $T {
 
 impl Int for $T {}
 
-impl Primitive for $T {
-    #[inline]
-    fn bits(_: Option<$T>) -> uint { bits }
-
-    #[inline]
-    fn bytes(_: Option<$T>) -> uint { bits / 8 }
-
-    #[inline]
-    fn is_signed(_: Option<$T>) -> bool { true }
-}
+impl Primitive for $T {}
 
 // String conversion functions and impl str -> num
 
@@ -640,13 +631,6 @@ mod tests {
     }
 
     #[test]
-    fn test_primitive() {
-        let none: Option<$T> = None;
-        assert_eq!(Primitive::bits(none), mem::size_of::<$T>() * 8);
-        assert_eq!(Primitive::bytes(none), mem::size_of::<$T>());
-    }
-
-    #[test]
     fn test_from_str() {
         assert_eq!(from_str::<$T>("0"), Some(0 as $T));
         assert_eq!(from_str::<$T>("3"), Some(3 as $T));