git ssb

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var LazyWatcher = require('./lib/lazy-watcher')
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var isReferenceType = require('./lib/is-reference-type')
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var resolve = require('./resolve')
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// TODO: reimplement using LazyWatcher
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module.exports = Dict
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function Dict (defaultValues) {
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  var object = Object.create({})
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  var sources = []
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  var releases = []
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  var binder = LazyWatcher(update, listen, unlisten)
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  binder.value = object
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  if (defaultValues) {
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    Object.keys(defaultValues).forEach(function (key) {
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      put(key, defaultValues[key])
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    })
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  }
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  var observable = function MutantDictionary (listener) {
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    if (!listener) {
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      return binder.getValue()
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    }
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    return binder.addListener(listener)
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  }
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  observable.put = function (key, valueOrObs) {
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    put(key, valueOrObs)
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    binder.broadcast()
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  }
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  observable.get = function (key) {
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    return sources[key]
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  }
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  observable.keys = function () {
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    return Object.keys(sources)
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  }
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  observable.clear = function () {
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    Object.keys(sources).forEach(function (key) {
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      tryInvoke(releases[key])
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      delete sources[key]
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      delete releases[key]
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      delete object[key]
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    })
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    binder.broadcast()
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  }
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  observable.delete = function (key) {
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    tryInvoke(releases[key])
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    delete sources[key]
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    delete releases[key]
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    delete object[key]
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    binder.broadcast()
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  }
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  observable.includes = function (valueOrObs) {
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    return !!~object.indexOf(valueOrObs)
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  }
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  observable.set = function (values) {
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    Object.keys(sources).forEach(function (key) {
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      tryInvoke(releases[key])
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      delete sources[key]
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      delete releases[key]
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      delete object[key]
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    })
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    Object.keys(values).forEach(function (key) {
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      put(key, values[key])
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    })
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    binder.broadcast()
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  }
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  return observable
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  // scoped
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  function put (key, valueOrObs) {
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    tryInvoke(releases[key])
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    sources[key] = valueOrObs
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    if (binder.live) {
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      releases[key] = bind(key, valueOrObs)
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    }
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    object[key] = resolve(valueOrObs)
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  }
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  function bind (key, valueOrObs) {
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    return typeof valueOrObs === 'function' ? valueOrObs(updateKey.bind(this, key)) : null
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  }
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  function updateKey (key, value) {
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    object[key] = value
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    binder.broadcast()
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  }
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  function listen () {
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    Object.keys(sources).forEach(function (key) {
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      releases[key] = bind(sources[key])
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    })
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  }
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  function unlisten () {
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    Object.keys(sources).forEach(function (key) {
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      tryInvoke(releases[key])
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      delete releases[key]
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    })
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  }
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  function update () {
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    var changed = false
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    Object.keys(sources).forEach(function (key) {
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      var newValue = resolve(sources[key])
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      if (newValue !== object[key] || isReferenceType(newValue)) {
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        object[key] = newValue
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        changed = true
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      }
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    })
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    return changed
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  }
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}
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function tryInvoke (func) {
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  if (typeof func === 'function') {
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    func()
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  }
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}
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