From 4222b6094ff3893fce350dffbcf7a02794f2bd93 Mon Sep 17 00:00:00 2001
From: LEXUGE <LEXUGEyky@outlook.com>
Date: Fri, 6 Apr 2018 17:06:33 +0800
Subject: [PATCH] delete the Neg trait bound for CheckedNeg

---
 src/ops/checked.rs | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/ops/checked.rs b/src/ops/checked.rs
index 97a96a5..de9de01 100644
--- a/src/ops/checked.rs
+++ b/src/ops/checked.rs
@@ -1,4 +1,4 @@
-use core::ops::{Add, Div, Mul, Neg, Rem, Shl, Shr, Sub};
+use core::ops::{Add, Div, Mul, Rem, Shl, Shr, Sub};
 
 /// Performs addition that returns `None` instead of wrapping around on
 /// overflow.
@@ -119,10 +119,16 @@ macro_rules! checked_impl_one_para {
     }
 }
 
-pub trait CheckedNeg: Sized + Neg<Output = Self> {
+pub trait CheckedNeg: Sized {
     fn checked_neg(&self) -> Option<Self>;
 }
 
+checked_impl_one_para!(CheckedNeg, checked_neg, u8);
+checked_impl_one_para!(CheckedNeg, checked_neg, u16);
+checked_impl_one_para!(CheckedNeg, checked_neg, u32);
+checked_impl_one_para!(CheckedNeg, checked_neg, u64);
+checked_impl_one_para!(CheckedNeg, checked_neg, usize);
+
 checked_impl_one_para!(CheckedNeg, checked_neg, i8);
 checked_impl_one_para!(CheckedNeg, checked_neg, i16);
 checked_impl_one_para!(CheckedNeg, checked_neg, i32);