splay/x/dict/index.js

Immutable splay trees.

var splay = require('../../index')

// get
// set
// read(from, to) w/ early terminate

module.exports = function () {
  return new Dict()
}

function Dict (tree) {
  this._tree = tree || splay(byKey)
}

Dict.prototype.get = function (key) {
  var root = this._tree = this._tree.access({ key: key })
  if (root.value.key === key) {
    return this._tree.value
  }
}

Dict.prototype.set = function (key, value) {
  this._tree = this._tree.uInsert({key: key, value: value})
  return new Dict(this._tree)
}

Dict.prototype.range = function (gte, lt, opts) {
  var res = []
  var root = this._tree
  root = root.access({ key: gte })
  while (!root.isEmpty()) {
    res.push(root.value)
    root = root._higher()
  }
  return res
}

function byKey (a, b) {
  console.log(a, b)
  if (a.key === b.key) return 0
  return a.key > b.key ? 1 : -1
}