sanctuary-js / sanctuary-pair Goto Github PK

const TOKEN = Object.freeze ({
  PARENT: 8,
  CHILD: 16,
})

// Token = { value: Any, type: Number }

//    parse :: Pair Ast (Array a) -> Token -> Pair Ast (Array a)
const parse = pair => token => {
  let ast = S.fst (pair), parent = S.snd (pair)

  switch (token.type) {
    case TOKEN.PARENT:
      parent = ast[token.value] = []
      break
    case TOKEN.CHILD:
      parent.push (token.value)
      break
    default:
      // skip token
  }

  return S.Pair (ast) (parent)
}

//    parser :: Array Token -> Ast
const parser = S.pipe ([
  timeStart ('parse'),
  S.reduce (parse) (S.Pair ({}) ([])),
  S.fst,
  timeEnd ('parse'),
])

parser (tokens)

  function Pair(fst) {
    return snd => {
      const pair = Object.create (prototype);
      if (Z.Setoid.test (fst) && Z.Setoid.test (snd)) {
        pair['fantasy-land/equals'] = Pair$prototype$equals;
        if (Z.Ord.test (fst) && Z.Ord.test (snd)) {
          pair['fantasy-land/lte'] = Pair$prototype$lte;
        }
      }
      if (Z.Semigroup.test (fst)) {
        if (Z.Semigroup.test (snd)) {
          pair['fantasy-land/concat'] = Pair$prototype$concat;
        }
        pair['fantasy-land/ap'] = Pair$prototype$ap;
        pair['fantasy-land/chain'] = Pair$prototype$chain;
      }
      pair.fst = fst;
      pair.snd = snd;
      return pair;
    };
  }

S.is($.Pair ($.Any) ($.Any) )