added kwarg constructor (JuliaArrays#13)

* added kwarg constructor

* test inference

Author: Pietro Vertechi

src/structarray.jl

@@ -22,6 +22,9 @@ StructArray{T}(c::C) where {T, C<:NamedTuple} =
     StructArray{createtype(T, eltypes(C)), length(size(c[1])), C}(c)
 StructArray(c::C) where {C<:NamedTuple} = StructArray{C}(c)
 
+StructArray{T}(; kwargs...) where {T} = StructArray{T}(values(kwargs))
+StructArray(; kwargs...) = StructArray(values(kwargs))
+
 StructArray{T}(args...) where {T} = StructArray{T}(NamedTuple{fields(T)}(args))
 @generated function StructArray{T}(::Base.UndefInitializer, d::Integer...) where {T}
     ex = Expr(:tuple, [:(Array{$(fieldtype(T, i))}(undef, sz)) for i in 1:fieldcount(T)]...)

test/runtests.jl

@@ -22,6 +22,19 @@ end
     @test t3 == t
 end
 
+@testset "kwargs constructor" begin
+    a = [1.2]
+    b = [2.3]
+    @test StructArray(a=a, b=b) == StructArray((a=a, b=b))
+    @test StructArray{ComplexF64}(re=a, im=b) == StructArray{ComplexF64}(a, b)
+    f1() = StructArray(a=[1.2], b=["test"])
+    f2() = StructArray{Pair}(first=[1.2], second=["test"])
+    t1 = @inferred f1()
+    t2 = @inferred f2()
+    @test t1 == StructArray((a=[1.2], b=["test"]))
+    @test t2 == StructArray{Pair}([1.2], ["test"])
+end
+
 @testset "complex" begin
     a, b = [1 2; 3 4], [4 5; 6 7]
     t = StructArray{ComplexF64}(a, b)