Construction of symmetry operations fails on addition of spaces to the input string

[brainandforce]

I've found that constructing a symmetry operation as described in README.md fails when any spaces are added to the string:

julia> using Crystalline

julia> op = S"x,y,z"
1 ──────────────────────────────── (x,y,z)
 ┌ 1  0  0 ╷ 0 ┐
 │ 0  1  0 ┆ 0 │
 └ 0  0  1 ╵ 0 ┘

julia> op = S"x, y, z"
Error showing value of type SymOperation{3}:
ERROR: DomainError with (1, 0):
trW = 1 for detW = 0 is not a valid symmetry operation; see ITA5 Vol A, Table 11.2.1.1
Stacktrace:
 [1] _throw_seitzerror(trW::Int64, detW::Int64)
   @ Crystalline ~/git/Crystalline.jl-0.3.9/src/notation.jl:399
 [2] rotation_order_3d
   @ ~/git/Crystalline.jl-0.3.9/src/notation.jl:315 [inlined]
 [3] seitz(op::SymOperation{3})
   @ Crystalline ~/git/Crystalline.jl-0.3.9/src/notation.jl:236
 [4] show(io::IOContext{Base.TTY}, #unused#::MIME{Symbol("text/plain")}, op::SymOperation{3})
   @ Crystalline ~/git/Crystalline.jl-0.3.9/src/show.jl:13

julia> op.rotation
3×3 Crystalline.SquareStaticMatrices.SqSMatrix{3, Float64} with indices SOneTo(3)×SOneTo(3):
 1.0  0.0  0.0
 0.0  0.0  0.0
 0.0  0.0  0.0

Although the exception seems to be thrown by the show() method, it looks like the actual problem is that the rotation matrix of the symmetry operation is constructed incorrectly, as I would have expected the first REPL output shown above.

Tested with both the latest release (0.3.9) and the latest commit on Julia 1.6.1.

[thchr]

Yeah, this would be good to support. The constructor indeed doesn't handle spaces but it could be easily adapted to do so. I'll push a fix today/tomorrow.

Thanks for reporting this :)

[thchr]

Oki, should be possible to add reasonable kinds of whitespace now (see 44b2b4e)
It will still throw a (parsing) error if you try to add whitespace after an element is complete (e.g. S"x ,y , z") - but I think that's reasonable to disallow: each entry must be terminated by a comma.