Cannot create chains in 0-dimensional spaces

[eschnett]

This fails:

julia> @basis 0
(⟨⟩, ⟨⟩)

julia> Chain{V,1}(v)
ERROR: DimensionMismatch("No precise constructor for SArray{Tuple{0},SubManifold{⟨⟩,0,0x0000000000000000},1,0} found. Length of input was 1.")
Stacktrace:
 [1] SArray{Tuple{0},SubManifold{⟨⟩,0,0x0000000000000000},1,0}(::Tuple{Tuple{Tuple{Tuple{SubManifold{⟨⟩,0,0x0000000000000000}}}}}) at /Users/eschnett/.julia/packages/StaticArrays/MB5hl/src/convert.jl:1
 [2] StaticArray at /Users/eschnett/.julia/packages/StaticArrays/MB5hl/src/convert.jl:4 [inlined] (repeats 4 times)
 [3] Chain{⟨⟩,1,𝕂,253} where 253 where 𝕂(::SubManifold{⟨⟩,0,0x0000000000000000}) at /Users/eschnett/.julia/packages/Grassmann/Of0BW/src/multivectors.jl:33
 [4] top-level scope at REPL[209]:1
 [5] eval(::Module, ::Any) at ./boot.jl:331
 [6] eval_user_input(::Any, ::REPL.REPLBackend) at /Users/eschnett/src/julia-1.4/usr/share/julia/stdlib/v1.4/REPL/src/REPL.jl:86
 [7] run_backend(::REPL.REPLBackend) at /Users/eschnett/.julia/packages/Revise/0meWR/src/Revise.jl:1075
 [8] top-level scope at none:0

This is of low priority to me.

[chakravala]

Zero dimensional generating spaces are not supported at this time, but they could possibly be supported in the future if it becomes truly necessary for some reason.

[chakravala]

@basis 0 works starting in v0.7.8 now, though I don't know why anyone would want that