From d64ecada19f603abe4a56461f27cd6cc92c4accd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Beno=C3=AEt=20Legat?= <benoit.legat@gmail.com>
Date: Wed, 12 Jun 2024 16:25:56 +0200
Subject: [PATCH] up

---
 src/arithmetic.jl    | 13 +++++++++++++
 src/sparse_coeffs.jl |  8 ++++++++
 2 files changed, 21 insertions(+)

diff --git a/src/arithmetic.jl b/src/arithmetic.jl
index 080cf77..85aaf6c 100644
--- a/src/arithmetic.jl
+++ b/src/arithmetic.jl
@@ -11,6 +11,10 @@ function _preallocate_output(X::AlgebraElement, Y::AlgebraElement, op)
     return similar(X, T)
 end
 
+function MA.promote_operation(::typeof(similar), ::Type{<:Vector}, ::Type{T}) where {T}
+    return Vector{T}
+end
+
 # module structure:
 
 Base.:*(X::AlgebraElement, a::Number) = a * X
@@ -27,12 +31,21 @@ function Base.:div(X::AlgebraElement, a::Number)
     return MA.operate_to!(_preallocate_output(X, a, div), div, X, a)
 end
 
+function MA.promote_operation(
+    op::Union{typeof(+),typeof(-)},
+    ::Type{AlgebraElement{A,T,VT}},
+    ::Type{AlgebraElement{A,S,VS}},
+) where {A,T,VT,S,VS}
+    U = MA.promote_operation(op, T, S)
+    return AlgebraElement{A,U,MA.promote_operation(similar, VT, U)}
+end
 function Base.:+(X::AlgebraElement, Y::AlgebraElement)
     return MA.operate_to!(_preallocate_output(X, Y, +), +, X, Y)
 end
 function Base.:-(X::AlgebraElement, Y::AlgebraElement)
     return MA.operate_to!(_preallocate_output(X, Y, -), -, X, Y)
 end
+
 function Base.:*(X::AlgebraElement, Y::AlgebraElement)
     return MA.operate_to!(_preallocate_output(X, Y, *), *, X, Y)
 end
diff --git a/src/sparse_coeffs.jl b/src/sparse_coeffs.jl
index bd828c9..c9ebeb0 100644
--- a/src/sparse_coeffs.jl
+++ b/src/sparse_coeffs.jl
@@ -42,6 +42,14 @@ function Base.zero(sc::SparseCoefficients)
     return SparseCoefficients(empty(keys(sc)), empty(values(sc)))
 end
 
+function MA.promote_operation(
+    ::typeof(similar),
+    ::Type{SparseCoefficients{K,V,Vk,Vv}},
+    ::Type{T},
+) where {K,V,Vk,Vv,T}
+    return SparseCoefficients{K,T,Vk,MA.promote_operation(similar, Vv, T)}
+end
+
 function Base.similar(s::SparseCoefficients, ::Type{T} = valtype(s)) where {T}
     return SparseCoefficients(similar(s.basis_elements), similar(s.values, T))
 end