add ConstructionBase interface

Project.toml

@@ -6,9 +6,11 @@ version = "1.1.1"
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
 Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
 Statistics = "10745b16-79ce-11e8-11f9-7d13ad32a3b2"
+ConstructionBase = "187b0558-2788-49d3-abe0-74a17ed4e7c9"
 
 [compat]
 julia = "1"
+ConstructionBase = "1.0, 1.1.0"
 
 [extras]
 BenchmarkTools = "6e4b80f9-dd63-53aa-95a3-0cdb28fa8baf"

src/StaticArrays.jl

@@ -10,6 +10,7 @@ import Base: getindex, setindex!, size, similar, vec, show, length, convert, pro
 
 import Statistics: mean
 
+using ConstructionBase
 using Random
 import Random: rand, randn, randexp, rand!, randn!, randexp!
 using Core.Compiler: return_type
@@ -143,6 +144,7 @@ include("qr.jl")
 include("deque.jl")
 include("flatten.jl")
 include("io.jl")
+include("constructorof.jl")
 
 if Base.VERSION >= v"1.4.2"
     include("precompile.jl")

src/constructorof.jl

@@ -0,0 +1,15 @@
+struct SArrayConstructor{S,N,L} end
+struct MArrayConstructor{S,N,L} end
+struct SizedArrayConstructor{S,N,M} end
+
+(::SArrayConstructor{S,N,L})(data::NTuple{L,T}) where {S,T,N,L} = SArray{S,T,N,L}(data)
+(::MArrayConstructor{S,N,L})(data::NTuple{L,T}) where {S,T,N,L} = MArray{S,T,N,L}(data)
+(::SizedArrayConstructor{S,N,M})(data::AbstractArray{T,M}) where {S,T,N,M} = 
+    SizedArray{S,T,N,M}(data)
+
+ConstructionBase.constructorof(sa::Type{<:SArray{S,<:Any,N,L}}) where {S,N,L} = 
+    SArrayConstructor{S,N,L}()
+ConstructionBase.constructorof(sa::Type{<:MArray{S,<:Any,N,L}}) where {S,N,L} = 
+    MArrayConstructor{S,N,L}()
+ConstructionBase.constructorof(sa::Type{<:SizedArray{S,<:Any,N,M}}) where {S,N,M} = 
+    SizedArrayConstructor{S,N,M}()

test/constructorof.jl

@@ -0,0 +1,17 @@
+using StaticArrays, Test, ConstructionBase
+
+@testset "constructorof" begin
+    sa = @SVector [2, 4, 6, 8]
+    sa2 = ConstructionBase.constructorof(typeof(sa))((3.0, 5.0, 7.0, 9.0))
+    @test sa2 === @SVector [3.0, 5.0, 7.0, 9.0]
+
+    ma = @MMatrix [2.0 4.0; 6.0 8.0]
+    ma2 = ConstructionBase.constructorof(typeof(ma))((1, 2, 3, 4))
+    @test ma2 isa MArray{Tuple{2,2},Int,2,4}
+    @test all(ma2 .=== @MMatrix [1 3; 2 4])
+
+    sz = SizedArray{Tuple{2,2}}([1 2;3 4])
+    sz2 = ConstructionBase.constructorof(typeof(sz))([:a :b; :c :d]) 
+    @test sz2 == SizedArray{Tuple{2,2}}([:a :b; :c :d])
+    @test typeof(sz2) <: SizedArray{Tuple{2,2},Symbol,2,2}
+end

test/runtests.jl

@@ -34,6 +34,7 @@ addtests("SUnitRange.jl")
 addtests("SizedArray.jl")
 addtests("SDiagonal.jl")
 addtests("SHermitianCompact.jl")
+addtests("constructorof.jl")
 
 addtests("ambiguities.jl")
 addtests("custom_types.jl")