fix symbol handling

Author: ChrisRackauckas

src/LabelledArrays.jl

@@ -64,8 +64,10 @@ function ArrayInterfaceCore.ismutable(::Type{<:LArray{T, N, D, Syms}}) where {T,
 end
 ArrayInterfaceCore.can_setindex(::Type{<:SLArray}) = false
 
+lenfun(x) = length(x)
+lenfun(::Symbol) = 1
 function ArrayInterfaceCore.undefmatrix(x::LArray{T, N, D, Syms}) where {T, N, D, Syms}
-    n = sum(length, Syms)
+    n = sum(lenfun, Syms)
     similar(x.__x, n, n)
 end
 

src/larray.jl

@@ -5,7 +5,7 @@ struct LArray{T, N, D <: AbstractArray{T, N}, Syms} <: DenseArray{T, N}
 end
 
 function LArray{T, N, D, Syms}(::UndefInitializer, n::Int64) where {T, N, D, Syms}
-    @assert sum(length, Syms) == n
+    @assert sum(lenfun, Syms) == n
     LArray{T, N, D, Syms}(similar(D, n))
 end
 

test/larrays.jl

@@ -16,9 +16,9 @@ using LabelledArrays, Test, InteractiveUtils
     syms = (:a, :b, :c)
     @test typeof(typeof(x)(undef, 3)) == typeof(x)
 
-    x = LabelledArrays.LArray{Float64, 1, Vector{Float64}, (x = 1:4, y = 5:8)}(undef, 8)
-    @test length(x) == 8
-    @test size(LabelledArrays.ArrayInterfaceCore.undefmatrix(x)) == (8, 8)
+    z = LabelledArrays.LArray{Float64, 1, Vector{Float64}, (x = 1:4, y = 5:8)}(undef, 8)
+    @test length(z) == 8
+    @test size(LabelledArrays.ArrayInterfaceCore.undefmatrix(z)) == (8, 8)
 
     for (i, s) in enumerate(syms)
         @show i, s