Drawing annotations

[teunbrand]

I'd be useful to construct layers purely from direct input and without mapping directly from data, like ggplot2::annotate() in R.
To kick off discussion about the syntax, I'll offer up MAPPING ... FROM null.

[teunbrand]

So to list a few options

Option 1:
Declare as FROM null. I'm not sure if MAPPING is a great fit in this case because we're providing literals instead of mappings.

DRAW point 
  MAPPING [1, 2] AS x, 2 AS y FROM null

Option 2:
Change the clause itself. It still has the mapping problem.

// Option 2A
ANNOTATE point
  MAPPING [1, 2] AS x, 2 AS y

We could also do this to mitigate the problem:

// Option 2B
ANNOTATE point
  SETTING x => [1, 2], y => 2

Option 3:
Replace mapping with another verb, that is mutually exclusive with mapping. Trying to use them both or the new verb with remapping causes error.

DRAW point
  SKETCH [1, 2] AS x, 2 AS y

I'm not married to 'annotate' or 'sketch'; they're up for discussion