@{%
const moo = require("moo");

// I'm not bothering to make each of these tokenizers full proof as I'm assuming the input
// will be an actual list of problems.
const lexer = moo.compile({
  sectionNum:     /[1-9]+\.[0-9]+/,
  date: /[0-9]+\/[0-9]+/,
  number: /[0-9]+/,
  newline: {match: '\n', lineBreaks: true},
  comment: /\([A-Za-z0-9\,]+\)/
});
%}

@lexer lexer

Sourcefile -> (Line "\n"):+

Line -> LineLabel "- " LineContents

LineLabel -> Section " " DueDate

Section -> "Section " %sectionNum

DueDate -> "(Due " %date ")"

LineContents -> "#" Problems

Problems -> (Problem ", "):+ Problem

Problem -> RequiredProblem 
    | NotRequiredProblem

RequiredProblem ->  %number "*"

NotRequiredProblem -> %number