# HG changeset patch
# User Tuomo Valkonen <tuomov@iki.fi>
# Date 1746947025 18000
# Node ID f75bf34adda0b8df216f055288638f5e00ebae98
# Parent  212f75931da0c55f81bbc66fe4de2bdfcf93757e
Switch from Cow to MyCow for DifferentiableImpl to avoid Clone trait bound

diff -r 212f75931da0 -r f75bf34adda0 src/mapping.rs
--- a/src/mapping.rs	Thu May 08 22:53:31 2025 -0500
+++ b/src/mapping.rs	Sun May 11 02:03:45 2025 -0500
@@ -3,12 +3,12 @@
 */
 
 use crate::error::DynResult;
+use crate::instance::MyCow;
 pub use crate::instance::{BasicDecomposition, Decomposition, Instance, Space};
 use crate::loc::Loc;
 use crate::norms::{Norm, NormExponent};
 use crate::operator_arithmetic::{Constant, Weighted};
 use crate::types::{ClosedMul, Float, Num};
-use std::borrow::Cow;
 use std::marker::PhantomData;
 use std::ops::Mul;
 
@@ -124,7 +124,7 @@
 impl<T, Domain> DifferentiableMapping<Domain> for T
 where
     Domain: Space,
-    T: Clone + Mapping<Domain> + DifferentiableImpl<Domain>,
+    T: Mapping<Domain> + DifferentiableImpl<Domain>,
 {
     type DerivativeDomain = T::Derivative;
     type Differential<'b>
@@ -139,26 +139,26 @@
 
     fn diff(self) -> Differential<'static, Domain, Self> {
         Differential {
-            g: Cow::Owned(self),
+            g: MyCow::Owned(self),
             _space: PhantomData,
         }
     }
 
     fn diff_ref(&self) -> Differential<'_, Domain, Self> {
         Differential {
-            g: Cow::Borrowed(self),
+            g: MyCow::Borrowed(self),
             _space: PhantomData,
         }
     }
 }
 
 /// Container for the differential [`Mapping`] of a [`DifferentiableMapping`].
-pub struct Differential<'a, X, G: Clone> {
-    g: Cow<'a, G>,
+pub struct Differential<'a, X, G> {
+    g: MyCow<'a, G>,
     _space: PhantomData<X>,
 }
 
-impl<'a, X, G: Clone> Differential<'a, X, G> {
+impl<'a, X, G> Differential<'a, X, G> {
     pub fn base_fn(&self) -> &G {
         &self.g
     }
@@ -167,7 +167,7 @@
 impl<'a, X, G> Mapping<X> for Differential<'a, X, G>
 where
     X: Space,
-    G: Clone + DifferentiableMapping<X>,
+    G: DifferentiableMapping<X>,
 {
     type Codomain = G::DerivativeDomain;
 
@@ -211,8 +211,8 @@
 impl<X: Space, F, G: Sized + Mapping<X, Codomain = Loc<1, F>>> FlattenCodomain<X, F> for G {}
 
 /// Container for dimensional slicing [`Loc`]`<N, F>` codomain of a [`Mapping`] to `F`.
-pub struct SlicedCodomain<'a, X, F, G: Clone, const N: usize> {
-    g: Cow<'a, G>,
+pub struct SlicedCodomain<'a, X, F, G, const N: usize> {
+    g: MyCow<'a, G>,
     slice: usize,
     _phantoms: PhantomData<(X, F)>,
 }
@@ -221,7 +221,7 @@
 where
     X: Space,
     F: Copy + Space,
-    G: Mapping<X, Codomain = Loc<N, F>> + Clone,
+    G: Mapping<X, Codomain = Loc<N, F>>,
 {
     type Codomain = F;
 
@@ -236,13 +236,13 @@
 /// An auto-trait for constructing a [`FlattenCodomain`] structure for
 /// flattening the codomain of a [`Mapping`] from [`Loc`]`<F, 1>` to `F`.
 pub trait SliceCodomain<X: Space, const N: usize, F: Copy = f64>:
-    Mapping<X, Codomain = Loc<N, F>> + Clone + Sized
+    Mapping<X, Codomain = Loc<N, F>> + Sized
 {
     /// Flatten the codomain from [`Loc`]`<F, 1>` to `F`.
     fn slice_codomain(self, slice: usize) -> SlicedCodomain<'static, X, F, Self, N> {
         assert!(slice < N);
         SlicedCodomain {
-            g: Cow::Owned(self),
+            g: MyCow::Owned(self),
             slice,
             _phantoms: PhantomData,
         }
@@ -252,14 +252,14 @@
     fn slice_codomain_ref(&self, slice: usize) -> SlicedCodomain<'_, X, F, Self, N> {
         assert!(slice < N);
         SlicedCodomain {
-            g: Cow::Borrowed(self),
+            g: MyCow::Borrowed(self),
             slice,
             _phantoms: PhantomData,
         }
     }
 }
 
-impl<X: Space, F: Copy, G: Sized + Mapping<X, Codomain = Loc<N, F>> + Clone, const N: usize>
+impl<X: Space, F: Copy, G: Sized + Mapping<X, Codomain = Loc<N, F>>, const N: usize>
     SliceCodomain<X, N, F> for G
 {
 }
@@ -337,7 +337,7 @@
 impl<'b, M, X, A> Lipschitz<M> for Differential<'b, X, A>
 where
     X: Space,
-    A: LipschitzDifferentiableImpl<X, M> + Clone,
+    A: LipschitzDifferentiableImpl<X, M>,
 {
     type FloatType = A::FloatType;
 
diff -r 212f75931da0 -r f75bf34adda0 src/mapping/dataterm.rs
--- a/src/mapping/dataterm.rs	Thu May 08 22:53:31 2025 -0500
+++ b/src/mapping/dataterm.rs	Sun May 11 02:03:45 2025 -0500
@@ -128,9 +128,9 @@
 impl<'a, F, X, Y, A, G> LipschitzDifferentiableImpl<X, X::NormExp> for DataTerm<F, X, A, G>
 where
     F: Float,
-    X: Normed<F> + Clone,
+    X: Normed<F>,
     Y: Normed<F>,
-    A: Clone + BoundedLinear<X, X::NormExp, L2, F, Codomain = Y>,
+    A: BoundedLinear<X, X::NormExp, L2, F, Codomain = Y>,
     G: Mapping<Y, Codomain = F> + LipschitzDifferentiableImpl<Y, Y::NormExp>,
     Self: DifferentiableImpl<X>,
 {
diff -r 212f75931da0 -r f75bf34adda0 src/operator_arithmetic.rs
--- a/src/operator_arithmetic.rs	Thu May 08 22:53:31 2025 -0500
+++ b/src/operator_arithmetic.rs	Sun May 11 02:03:45 2025 -0500
@@ -2,72 +2,74 @@
 Arithmetic of [`Mapping`]s.
  */
 
-use serde::Serialize;
+use crate::instance::{Instance, Space};
+use crate::mapping::{DifferentiableImpl, DifferentiableMapping, Mapping};
 use crate::types::*;
-use crate::instance::{Space, Instance};
-use crate::mapping::{Mapping, DifferentiableImpl, DifferentiableMapping};
+use serde::Serialize;
 
 /// A trait for encoding constant [`Float`] values
-pub trait Constant : Copy + Sync + Send + 'static + std::fmt::Debug + Into<Self::Type> {
+pub trait Constant: Copy + Sync + Send + 'static + std::fmt::Debug + Into<Self::Type> {
     /// The type of the value
-    type Type : Float;
+    type Type: Float;
     /// Returns the value of the constant
     fn value(&self) -> Self::Type;
 }
 
-impl<F : Float> Constant for F {
+impl<F: Float> Constant for F {
     type Type = F;
     #[inline]
-    fn value(&self) -> F { *self }
+    fn value(&self) -> F {
+        *self
+    }
 }
 
 /// Weighting of a [`Mapping`] by scalar multiplication.
-#[derive(Copy,Clone,Debug,Serialize)]
-pub struct Weighted<T, C : Constant> {
+#[derive(Copy, Clone, Debug, Serialize)]
+pub struct Weighted<T, C: Constant> {
     /// The weight
-    pub weight : C,
+    pub weight: C,
     /// The base [`Mapping`] being weighted.
-    pub base_fn : T,
+    pub base_fn: T,
 }
 
 impl<T, C> Weighted<T, C>
 where
-    C : Constant,
+    C: Constant,
 {
     /// Construct from an iterator.
-    pub fn new(weight : C, base_fn : T) -> Self {
-        Weighted{ weight, base_fn }
+    pub fn new(weight: C, base_fn: T) -> Self {
+        Weighted { weight, base_fn }
     }
 }
 
 impl<'a, T, V, D, F, C> Mapping<D> for Weighted<T, C>
 where
-    F : Float,
-    D : Space,
-    T : Mapping<D, Codomain=V>,
-    V : Space + ClosedMul<F>,
-    C : Constant<Type=F>
+    F: Float,
+    D: Space,
+    T: Mapping<D, Codomain = V>,
+    V: Space + ClosedMul<F>,
+    C: Constant<Type = F>,
 {
     type Codomain = V;
 
     #[inline]
-    fn apply<I : Instance<D>>(&self, x : I) -> Self::Codomain {
+    fn apply<I: Instance<D>>(&self, x: I) -> Self::Codomain {
         self.base_fn.apply(x) * self.weight.value()
     }
 }
 
 impl<'a, T, V, D, F, C> DifferentiableImpl<D> for Weighted<T, C>
 where
-    F : Float,
-    D : Space,
-    T : DifferentiableMapping<D, DerivativeDomain=V>,
-    V : Space + std::ops::Mul<F, Output=V>,
-    C : Constant<Type=F>
+    F: Float,
+    D: Space,
+    T: DifferentiableMapping<D, DerivativeDomain = V>,
+    V: Space + std::ops::Mul<F, Output = V>,
+    C: Constant<Type = F>,
 {
     type Derivative = V;
 
     #[inline]
-    fn differential_impl<I : Instance<D>>(&self, x : I) -> Self::Derivative {
+    fn differential_impl<I: Instance<D>>(&self, x: I) -> Self::Derivative {
         self.base_fn.differential(x) * self.weight.value()
     }
 }
@@ -76,9 +78,9 @@
 #[derive(Serialize, Debug, Clone)]
 pub struct MappingSum<M>(Vec<M>);
 
-impl< M> MappingSum<M> {
+impl<M> MappingSum<M> {
     /// Construct from an iterator.
-    pub fn new<I : IntoIterator<Item = M>>(iter : I) -> Self {
+    pub fn new<I: IntoIterator<Item = M>>(iter: I) -> Self {
         MappingSum(iter.into_iter().collect())
     }
 
@@ -90,27 +92,27 @@
 
 impl<Domain, M> Mapping<Domain> for MappingSum<M>
 where
-    Domain : Space + Clone,
-    M : Mapping<Domain>,
-    M::Codomain : std::iter::Sum + Clone
+    Domain: Space + Clone,
+    M: Mapping<Domain>,
+    M::Codomain: std::iter::Sum + Clone,
 {
     type Codomain = M::Codomain;
 
-    fn apply<I : Instance<Domain>>(&self, x : I) -> Self::Codomain {
+    fn apply<I: Instance<Domain>>(&self, x: I) -> Self::Codomain {
         let xr = x.ref_instance();
         self.0.iter().map(|c| c.apply(xr)).sum()
     }
 }
 
-impl<Domain, M> DifferentiableImpl<Domain> for MappingSum< M>
+impl<Domain, M> DifferentiableImpl<Domain> for MappingSum<M>
 where
-    Domain : Space + Clone,
-    M : DifferentiableMapping<Domain>,
-    M :: DerivativeDomain : std::iter::Sum
+    Domain: Space,
+    M: DifferentiableMapping<Domain>,
+    M::DerivativeDomain: std::iter::Sum,
 {
     type Derivative = M::DerivativeDomain;
 
-    fn differential_impl<I : Instance<Domain>>(&self, x : I) -> Self::Derivative {
+    fn differential_impl<I: Instance<Domain>>(&self, x: I) -> Self::Derivative {
         let xr = x.ref_instance();
         self.0.iter().map(|c| c.differential(xr)).sum()
     }