Doc comments not highlighted

[nwolverson]

(OK so I only tested this in vscode, which is generated from this, and it seems to be different on GH)

With a space, doc comments get highlighted

-- | blah

but without, they don't highlight as comment - and I think this is valid -

--| blah

This may be related to the fact that other symbols prevent highlighting as comment, but not letters:

--% this is not comment

--This is comment

[wclr]

--This is comment or --% this is not comment (comments without space after --) are a valid comment for the language parser, do you think they should be highlighted as comments?

[nwolverson]

It should ideally be whatever purs does