--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/Grids/zero_dim_grid.jl	Sat May 20 15:15:22 2023 +0200
@@ -0,0 +1,27 @@
+"""
+    ZeroDimGrid{T} <: Grid{T,0}
+
+A zero dimensional grid consisting of a single point.
+"""
+struct ZeroDimGrid{T} <: Grid{T,0}
+    point::T
+end
+
+# Indexing interface
+Base.getindex(g::ZeroDimGrid) = g.point
+Base.eachindex(g::ZeroDimGrid) = CartesianIndices(())
+
+# Iteration interface
+Base.iterate(g::ZeroDimGrid) = (g.point, nothing)
+Base.iterate(g::ZeroDimGrid, ::Any) = nothing
+
+Base.IteratorSize(::Type{<:ZeroDimGrid}) = Base.HasShape{0}()
+Base.length(g::ZeroDimGrid) = 1
+Base.size(g::ZeroDimGrid) = ()
+
+
+refine(g::ZeroDimGrid, ::Int) = g
+coarsen(g::ZeroDimGrid, ::Int) = g
+
+boundary_identifiers(g::ZeroDimGrid) = ()
+boundary_grid(g::ZeroDimGrid, ::Any) = throw(ArgumentError("ZeroDimGrid has no boundaries"))