More ctor fussiness

Author: kshyatt

src/planar/preprocessors.jl

@@ -184,7 +184,7 @@ function _construct_braidingtensors!(ex, preargs, indexmap, non_braiding) # ex i
             if foundV1 && foundV2
                 s = gensym(:τ)
                 storageex = Expr(:call, GlobalRef(TensorKit, :promote_storagetype), non_braiding...)
-                constructex = Expr(:call, GlobalRef(TensorKit, :BraidingTensor), V1, V2, storageex)
+                constructex = Expr(:call, GlobalRef(TensorKit, :BraidingTensor), storageex, V1, V2)
                 push!(preargs, Expr(:(=), s, constructex))
                 obj = _is_adjoint(obj) ? _add_adjoint(s) : s
                 success = true

src/tensors/braidingtensor.jl

@@ -53,6 +53,23 @@ function BraidingTensor{T}(V::HomSpace, adjoint::Bool = false) where {T}
         throw(SpaceMismatch("Cannot define a braiding on $V"))
     return BraidingTensor{T}(V[2], V[1], adjoint)
 end
+# these are here to make the preprocessing for `@planar` expressions less painful
+function BraidingTensor(TorA::Type, V1::S, V2::S, adjoint::Bool = false) where {S <: IndexSpace}
+    T = eltype(TorA)
+    TA = storagetype(TorA)
+    return BraidingTensor{T, S, TA}(V1, V2, adjoint)
+end
+function BraidingTensor(TorA::Type, V1::IndexSpace, V2::IndexSpace, adjoint::Bool = false)
+    return BraidingTensor(TorA, promote(V1, V2)..., adjoint)
+end
+function BraidingTensor(TorA::Type, V::HomSpace, adjoint::Bool = false)
+    domain(V) == reverse(codomain(V)) ||
+        throw(SpaceMismatch("Cannot define a braiding on $V"))
+    T = eltype(TorA)
+    S = spacetype(V[2])
+    TA = storagetype(TorA)
+    return BraidingTensor{T, S, TA}(V[2], V[1], adjoint)
+end
 function Base.adjoint(b::BraidingTensor{T, S, A}) where {T, S, A}
     return BraidingTensor{T, S, A}(b.V1, b.V2, !b.adjoint)
 end