git ssb

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var LazyWatcher = require('./lib/lazy-watcher')
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var resolve = require('./resolve')
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var isObservable = require('./is-observable')
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module.exports = ProxyDict
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function ProxyDict (source, opts) {
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  var releases = []
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  var binder = LazyWatcher(update, listen, unlisten)
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  binder.value = resolve(source)
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  if (opts && opts.nextTick) {
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    binder.nextTick = true
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  }
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  var observable = function MutantProxyDict (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.get = function (key) {
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    if (isObservable(source) && source.get) {
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      return source.get(key)
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    } else if (resolve(source)) {
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      return resolve(source)[key]
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    }
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  }
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  observable.keys = function () {
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    if (isObservable(source) && source.keys) {
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      return resolve(source.keys)
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    } else if (resolve(source)) {
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      return Object.keys(resolve(source))
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    } else {
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      return []
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    }
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  }
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  observable.has = function (key) {
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    if (isObservable(source) && source.has) {
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      return source.has(key)
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    } else if (resolve(source)) {
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      return key in resolve(source)
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    }
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  }
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  observable.set = function (newSource) {
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    unlisten()
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    source = newSource
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    if (binder.live) {
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      listen()
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    }
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    binder.onUpdate()
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  }
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  return observable
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  // scoped
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  function listen () {
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    if (isObservable(source)) {
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      releases.push(
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        source(binder.onUpdate)
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      )
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    }
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  }
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  function unlisten () {
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    while (releases.length) {
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      releases.pop()()
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    }
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  }
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  function update () {
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    binder.value = resolve(source) || {}
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    return true
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  }
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}
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