--- a/src/SbpOperators/boundaryops/boundary_restriction.jl	Mon Nov 23 21:19:08 2020 +0100
+++ b/src/SbpOperators/boundaryops/boundary_restriction.jl	Tue Nov 24 15:28:10 2020 +0100
@@ -1,3 +1,8 @@
+"""
+    boundary_restriction(grid,closureStencil,boundary)
+
+Creates a BoundaryRestriction operator for the specified boundary
+"""
 function boundary_restriction(grid::EquidistantGrid{1,T}, closureStencil::Stencil{T,M}, boundary::CartesianBoundary{1}) where {T,M}
     r = region(boundary)
     return e = BoundaryRestriction(grid, closureStencil, r())
@@ -16,15 +21,14 @@
     I = IdentityMapping{T}(size(restrict(grid,1)))
     return I⊗e
 end
-
 export boundary_restriction
 
 """
-    BoundaryRestriction{T,N,R} <: TensorMapping{T,1,1}
+    BoundaryRestriction{T,N,R} <: TensorMapping{T,0,1}
 
 Implements the boundary operator `e` as a TensorMapping
 """
-struct BoundaryRestriction{T,M,R<:Region} <: TensorMapping{T,1,1}
+struct BoundaryRestriction{T,M,R<:Region} <: TensorMapping{T,0,1}
     stencil::Stencil{T,M}
     size::NTuple{1,Int}
 end
@@ -34,9 +38,13 @@
     return BoundaryRestriction{T,M,typeof(region)}(closureStencil,size(grid))
 end
 
-LazyTensors.range_size(e::BoundaryRestriction) = (1,)
+LazyTensors.range_size(e::BoundaryRestriction) = (0,)
 LazyTensors.domain_size(e::BoundaryRestriction) = e.size
 
+# TODO: Currently not working.
+# We need to handle getindex for LazyTensorMappingApplication such that we pass more #indices than the
+# range size of the TensorMapping. Or we need to be able to handle the case where we dont pass any index, for
+# 0-dimensional tensormappings.
 " Restricts a grid function v on a grid of size m to the scalar element v[1]"
 function LazyTensors.apply(e::BoundaryRestriction{T,M,Lower}, v::AbstractVector{T}, i::Index{Lower}) where {T,M}
     @boundscheck if Int(i)!=1
@@ -55,18 +63,18 @@
 
 " Transpose of a restriction is an inflation or prolongation.
   Inflates the scalar (1-element) vector to a vector of size of the grid"
-function LazyTensors.apply_transpose(e::BoundaryRestriction{T,M,Lower}, v::AbstractVector{T}, i) where {T,M}
+function LazyTensors.apply_transpose(e::BoundaryRestriction{T,M,Lower}, v::AbstractArray{T,0}, i) where {T,M}
     @boundscheck if !(0 < Int(i) <= e.size[1])
         throw(BoundsError())
     end
-    return e.stencil[Int(i)-1]*v[1]
+    return e.stencil[Int(i)-1]*v[]
 end
 
 " Transpose of a restriction is an inflation or prolongation.
   Inflates the scalar (1-element) vector to a vector of size of the grid"
-function LazyTensors.apply_transpose(e::BoundaryRestriction{T,M,Upper}, v::AbstractVector{T}, i) where {T,M}
+function LazyTensors.apply_transpose(e::BoundaryRestriction{T,M,Upper}, v::AbstractArray{T,0}, i) where {T,M}
     @boundscheck if !(0 < Int(i) <= e.size[1])
         throw(BoundsError())
     end
-    return e.stencil[e.size[1] - Int(i)]*v[1]
+    return e.stencil[e.size[1] - Int(i)]*v[]
 end