basicParser.js

function value (line) {
  const [, t, c, v] = line.split(" ")
  return {t, p: {cursor: c.split("::"), value: v}}
}

function header (line) {
  const [,...rest] = line.split(" ")
  const c = rest.join(" ")
  return {t: "header", c}
}

function liChecked (line) {
  const [,,...rest] = line.split(" ")
  return {t: "list-item", p: { checked: true }, c: rest.join(" ")}
}

function input (line) {
  const [, type, name, ...label] = line.split(" ")
  return {t: "input", p: {type}, c: label.join(" ")}
}

function watch (line) {
  const [, type, cursor, value, ...rest] = line.split(" ")
  return {t: "watch", p: {cursor: cursor.split("::")}, c: rest.join(" ")}
}

function toAst(line) {
  if (line === "" || line.startsWith("//")) return null
  if (line.startsWith("- value"))           return value(line)
  if (line.startsWith("- watch"))           return watch(line)
  if (line.startsWith("# "))                return header(line)
  if (line.startsWith("* [x]"))             return liChecked(line)
  if (line.startsWith("~ "))                return input(line)
  return line
}

function _Parse(rawLines = [], parsedLines=[]) {
  if (!rawLines.length) return parsedLines;
  let currentLine = toAst(rawLines.pop().trim());
  if (currentLine == null) return _Parse(rawLines, parsedLines)
  return _Parse(rawLines, [currentLine, ...parsedLines])
}

function Parse (doc) {
  let lines = doc[0].split("\n")
  return _Parse(lines)
}

// Symbol | What it is
// -      | something to do with data
// ~      | an input
// #      | heading
// *      | list item

let result = Parse`
  - value status default
  - value fields::product 162
  
  # This is a heading

  * [x] this is a checked list
  * [x] woot woot woot
  * [x] ehrmagard

  ~ text full_name Full Name
  ~ email email Email
  ~ password password Password
  
  - watch status default button 1
  - watch status processing button 2
  - watch status success button 2
`

console.log(result)