Add length method for ViewAxis

Author: dingraha

src/axis.jl

@@ -122,6 +122,8 @@ ViewAxis{Inds,IdxMap,Ax}() where {Inds,IdxMap,Ax} = ViewAxis(Inds, Ax())
 ViewAxis(Inds, IdxMap) = ViewAxis(Inds, Axis(IdxMap))
 ViewAxis(Inds) = Inds
 
+Base.length(ax::ViewAxis{Inds}) where Inds = length(Inds)
+
 const View = ViewAxis
 const NullOrFlatView{Inds,IdxMap} = ViewAxis{Inds,IdxMap,<:NullorFlatAxis}
 

test/runtests.jl

@@ -178,6 +178,8 @@ end
     x = ComponentArray(b=1, a=2)
     @test merge(NamedTuple(), x) == NamedTuple(x)
     @test kw_fun(; x...) == 2
+
+    @test length(ViewAxis(2:7, ShapedAxis((2,3)))) == 6
 end
 
 @testset "Get" begin
@@ -388,6 +390,8 @@ end
     end
 end
 
+
+
 @testset "Similar" begin
     @test similar(ca) isa typeof(ca)
     @test similar(ca2) isa typeof(ca2)