wip

lib/ratio_ops/src/ratio.rs

@@ -68,54 +68,57 @@ impl_ratio_method!(Add,add,add_ratio);
 impl_ratio_method!(Sub,sub,sub_ratio);
 impl_ratio_method!(Rem,rem,rem_ratio);
 
-/// Comparing two ratios needs to know the parity of the denominators
-/// For signed integers this can be implemented with is_negative()
-pub trait Parity{
-	fn parity(&self)->bool;
+/// The denominator cannot be negative
+/// otherwise cross-multiplying changes the comparison
+pub trait ToUnsigned{
+	type Unsigned;
+	fn to_unsigned(self)->(bool,Self::Unsigned);
 }
-macro_rules! impl_parity_unsigned{
+macro_rules! impl_to_unsigned_unsigned{
 	($($type:ty),*)=>{
 		$(
-		impl Parity for $type{
-			fn parity(&self)->bool{
-				false
+		impl ToUnsigned for $type{
+			type Unsigned=Self;
+			fn to_unsigned(self)->(bool,Self::Unsigned){
+				(false,self)
 			}
 		}
 		)*
 	};
 }
-macro_rules! impl_parity_signed{
-	($($type:ty),*)=>{
+macro_rules! impl_to_unsigned_signed{
+	($(($type:ty,$unsigned:ty)),*)=>{
 		$(
-		impl Parity for $type{
-			fn parity(&self)->bool{
-				self.is_negative()
+		impl ToUnsigned for $type{
+			type Unsigned=$unsigned;
+			fn to_unsigned(self)->(bool,Self::Unsigned){
+				(self.is_negative(),self.unsigned_abs())
 			}
 		}
 		)*
 	};
 }
-macro_rules! impl_parity_float{
+macro_rules! impl_to_unsigned_float{
 	($($type:ty),*)=>{
 		$(
-		impl Parity for $type{
-			fn parity(&self)->bool{
-				self.is_sign_negative()
+		impl ToUnsigned for $type{
+			type Unsigned=Self;
+			fn to_unsigned(self)->(bool,Self::Unsigned){
+				(self.is_sign_negative(),-self)
 			}
 		}
 		)*
 	};
 }
-
-impl_parity_unsigned!(u8,u16,u32,u64,u128,usize);
-impl_parity_signed!(i8,i16,i32,i64,i128,isize);
-impl_parity_float!(f32,f64);
+impl_to_unsigned_unsigned!(u8,u16,u32,u64,u128,usize);
+impl_to_unsigned_signed!((i8,u8),(i16,u16),(i32,u32),(i64,u64),(i128,u128),(isize,usize));
+impl_to_unsigned_float!(f32,f64);
 
 macro_rules! impl_ratio_ord_method{
 	($method:ident, $ratio_method:ident, $output:ty)=>{
-		impl<LhsNum,LhsDen:Parity> Ratio<LhsNum,LhsDen>{
+		impl<LhsNum,LhsDen:ToUnsigned> Ratio<LhsNum,LhsDen>{
 			#[inline]
-			pub fn $ratio_method<RhsNum,RhsDen:Parity,T>(self,rhs:Ratio<RhsNum,RhsDen>)->$output
+			pub fn $ratio_method<RhsNum,RhsDen:ToUnsigned,T>(self,rhs:Ratio<RhsNum,RhsDen>)->$output
 				where
 					LhsNum:core::ops::Mul<RhsDen,Output=T>,
 					LhsDen:core::ops::Mul<RhsNum,Output=T>,
@@ -273,9 +276,9 @@ impl<Num,Den> Eq for Ratio<Num,Den> where Self:PartialEq{}
 impl<LhsNum,LhsDen,RhsNum,RhsDen,T,U> PartialOrd<Ratio<RhsNum,RhsDen>> for Ratio<LhsNum,LhsDen>
 	where
 		LhsNum:Copy,
-		LhsDen:Copy+Parity,
+		LhsDen:Copy+ToUnsigned,
 		RhsNum:Copy,
-		RhsDen:Copy+Parity,
+		RhsDen:Copy+ToUnsigned,
 		LhsNum:core::ops::Mul<RhsDen,Output=T>,
 		LhsDen:core::ops::Mul<RhsNum,Output=T>,
 		RhsNum:core::ops::Mul<LhsDen,Output=U>,
@@ -290,7 +293,7 @@ impl<LhsNum,LhsDen,RhsNum,RhsDen,T,U> PartialOrd<Ratio<RhsNum,RhsDen>> for Ratio
 impl<Num,Den,T> Ord for Ratio<Num,Den>
 	where
 		Num:Copy,
-		Den:Copy+Parity,
+		Den:Copy+ToUnsigned,
 		Num:core::ops::Mul<Den,Output=T>,
 		Den:core::ops::Mul<Num,Output=T>,
 		T:Ord,