Change order @planar preprocessors

The braidingtensors are now instantiated first, such that contractcheck can now be used.
Fixes #92.

src/planar/macros.jl

@@ -21,9 +21,10 @@ function planarparser(planarexpr, kwargs...)
     push!(parser.postprocessors, ex -> _free_temporaries(ex, temporaries))
     push!(parser.postprocessors, _insert_planar_operations)
 
-    for kw in kwargs
-        name, val = kw
-
+    # braiding tensors need to be instantiated before kwargs are processed
+    push!(parser.preprocessors, _construct_braidingtensors)
+
+    for (name, val) in kwargs
         if name == :order
             isexpr(val, :tuple) ||
                 throw(ArgumentError("Invalid use of `order`, should be `order=(...,)`"))
@@ -61,9 +62,7 @@ function planarparser(planarexpr, kwargs...)
             throw(ArgumentError("Unknown keyword argument `name`."))
         end
     end
-    braidingtensors = Vector{Any}()
-
-    push!(parser.preprocessors, _construct_braidingtensors)
+
     treebuilder = parser.contractiontreebuilder
     treesorter = parser.contractiontreesorter
     costcheck = parser.contractioncostcheck

src/planar/preprocessors.jl

@@ -179,7 +179,7 @@ function _construct_braidingtensors(ex::Expr)
         push!(construct_expr.args, indexmap[i1b])
         push!(construct_expr.args, indexmap[i2b])
         s = gensym(:τ)
-        push!(pre.args, Expr(:(=), s, construct_expr))
+        push!(pre.args, :(@notensor $s = $construct_expr))
         ex = TO.replacetensorobjects(ex) do o, l, r
             if o == obj && l == leftind && r == rightind
                 return obj == :τ ? s : Expr(TO.prime, s)

test/planar.jl

@@ -71,6 +71,29 @@ end
 
 @testset "@planar" verbose = true begin
     T = ComplexF64
+
+    @testset "contractcheck" begin
+        V = ℂ^2
+        A = TensorMap(rand, T, V ⊗ V ← V)
+        B = TensorMap(rand, T, V ⊗ V ← V')
+        @tensor C1[i j; k l] := A[i j; m] * B[k l; m]
+        @tensor contractcheck=true C2[i j; k l] := A[i j; m] * B[k l; m]
+        @test C1 ≈ C2
+        B2 = TensorMap(rand, T, V ⊗ V ← V) # wrong duality for third space
+        @test_throws SpaceMismatch("incompatible spaces for m: $V ≠ $(V')") begin
+            @tensor contractcheck = true C3[i j; k l] := A[i j; m] * B2[k l; m]
+        end
+
+        A = TensorMap(rand, T, V ← V ⊗ V)
+        B = TensorMap(rand, T, V ⊗ V ← V)
+        @planar C1[i; j] := A[i; k l] * τ[k l; m n] * B[m n; j]
+        @planar contractcheck=true C2[i; j] := A[i; k l] * τ[k l; m n] * B[m n; j]
+        @test C1 ≈ C2
+        @test_throws SpaceMismatch("incompatible spaces for l: $V ≠ $(V')") begin
+            @planar contractcheck=true C3[i; j] := A[i; k l] * τ[k l; m n] * B[n j; m]
+        end
+    end
+
     @testset "MPS networks" begin
         P = ℂ^2
         Vmps = ℂ^12