switched ϵ,∂ printing and improved ∪,∩

Project.toml

@@ -1,7 +1,7 @@
 name = "DirectSum"
 uuid = "22fd7b30-a8c0-5bf2-aabe-97783860d07c"
 authors = ["Michael Reed"]
-version = "0.2.4"
+version = "0.2.5"
 
 [deps]
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"

src/indices.jl

@@ -10,7 +10,7 @@ end
 @pure Base.ndims(::Dim{N}) where N = N
 
 # vector and co-vector prefix
-const pre = ("v","w","ϵ","∂")
+const pre = ("v","w","∂","ϵ")
 
 # vector space and dual-space symbols
 const vsn = (:V,:VV,:W)
@@ -126,10 +126,10 @@ end
 @inline printindices(io::IO,a::VTI,b::VTI,l::Bool=false,e::String=pre[1],f::String=pre[2]) = printindices(io,a,b,Int[],Int[],l,e,f)
 @inline function printindices(io::IO,a::VTI,b::VTI,c::VTI,d::VTI,l::Bool=false,e::String=pre[1],f::String=pre[2],g::String=pre[3],h::String=pre[4])
     A,B,C,D = isempty(a),!isempty(b),!isempty(c),!isempty(d)
+    D && printindices(io,d,l,h)
+    C && printindices(io,c,l,g)
     !((B || C || D) && A) && printindices(io,a,l,e)
     B && printindices(io,b,l,f)
-    C && printindices(io,c,l,g)
-    D && printindices(io,d,l,h)
 end
 @pure printindices(io::IO,V::T,e::Bits,label::Bool=false) where T<:VectorSpace = printlabel(io,V,e,label,pre...)
 

src/operations.jl

@@ -89,6 +89,9 @@ for op ∈ (:*,:∪)
     end
 end
 
+∪(x::T) where T<:VectorSpace = x
+∪(a::A,b::B,c::C...) where {A<:VectorSpace,B<:VectorSpace,C<:VectorSpace} = ∪(a∪b,c...)
+
 @pure ∩(a::T,::Q) where {T<:VectorSpace{N,M,S},Q<:VectorSpace{N,M,S}} where {N,M,S} = a
 @pure ∩(a::T,::S) where {T<:VectorSpace{N},S<:VectorSpace{N}} where N = V0
 @pure function ∩(a::T,b::S) where {T<:VectorSpace{N1,M1,S1},S<:VectorSpace{N2,M2,S2}} where {N1,M1,S1,N2,M2,S2}
@@ -104,6 +107,9 @@ end
     end
 end
 
+∩(x::T) where T<:VectorSpace = x
+∩(a::A,b::B,c::C...) where {A<:VectorSpace,B<:VectorSpace,C<:VectorSpace} = ∩(a∩b,c...)
+
 @pure ⊇(a::T,b::S) where {T<:VectorSpace,S<:VectorSpace} = b ⊆ a
 @pure ⊆(::T,::Q) where {T<:VectorSpace{N,M,S},Q<:VectorSpace{N,M,S}} where {N,M,S} = true
 @pure ⊆(::T,::S) where {T<:VectorSpace{N},S<:VectorSpace{N}} where N = false