support named properties of staticvectors

JuliaObjects · Jan 26, 2023 · 72e3ce6 · 72e3ce6
1 parent 65dcf63
commit 72e3ce6
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diff --git a/ext/StaticArraysExt.jl b/ext/StaticArraysExt.jl
@@ -12,4 +12,19 @@ ConstructionBase.constructorof(sa::Type{<:SizedArray{S}}) where {S} = SizedArray
 ConstructionBase.constructorof(::Type{<:SVector}) = SVector
 ConstructionBase.constructorof(::Type{<:MVector}) = MVector
 
+# set properties by name: x, y, z, w
+@generated function ConstructionBase.setproperties(obj::Union{SVector{N}, MVector{N}}, patch::NamedTuple{KS}) where {N, KS}
+    if KS == (:data,)
+        :( constructorof(typeof(obj))(only(patch)) )
+    else
+        propnames = (:x, :y, :z, :w)[1:N]
+        KS ⊆ propnames || error("type $obj does not have properties $(join(KS, ", "))")
+        field_exprs = map(enumerate(propnames)) do (i, p)
+            from = p ∈ KS ? :patch : :obj
+            :( $from.$p )
+        end
+        :( constructorof(typeof(obj))($(field_exprs...)) )
+    end
+end
+
 end
diff --git a/test/runtests.jl b/test/runtests.jl
@@ -497,6 +497,13 @@ if isdefined(Base, :get_extension)  # some 1.9 version
             @test ConstructionBase.constructorof(T{3, X} where {X})((1, 2))::T == T((1, 2))
             @test ConstructionBase.constructorof(T{X, Symbol} where {X})((1, 2, 3))::T == T((1, 2, 3))
         end
+
+        sv = SVector(1, 2)
+        @test SVector(3.0, 2.0) === @inferred setproperties(sv, x = 3.0)
+        @test SVector(3.0, 5.0) === @inferred setproperties(sv, x = 3.0, y = 5.0)
+        @test SVector(-1.0, -2.0) === @inferred setproperties(sv, data = (-1.0, -2))
+
+        @test_throws "does not have properties z" setproperties(sv, z = 3.0)
     end
 
     @testset "intervalsets" begin