No, you don't need '[' and ']' ? Also you don't need the '&' to get the equivalent of the above, but might have to add support for spaces?
> \p{L} or \p{Letter}: any kind of letter from any language.
vs
> \p{L&} or \p{Letter&}: a letter that exists in lowercase and uppercase variants (combination of Ll, Lu and Lt).
Along with:
> \p{Z} or \p{Separator}: any kind of whitespace or invisible separator.
Considering the op matches everything printable, including whitespace (or actually just space, not tab), numbers and punctation, I think the equivalent would be "\X" ?
