Cool! Thanks for some more reading and inspiration.

Here's what I have in my notes buffer; I hadn't gotten much further than this.

  Ssn: /([0-9]{9})|([0-9]{3})-([0-9]{2})-([0-9]{4})/\1\2\3/
  People: Table
      first: String
      last: String
      dob: Date
      ssn: SSN

  Csv
      headings: True
      load people.csv
          as: People
      select first last dob
      filter dob.age > 21

Well, I had some discussion, alternate forms of the syntax, links to prior art, etc, but not much else worth sharing.

Will have to add your TreeNotation and Ohayo to that list, as well as these other links you've shared.