git ssb

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var Value = require('./value')
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module.exports = Uniq
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function Uniq (obs) {
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  var object = []
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  update()
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  var observable = Value(object)
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  var broadcast = observable.set
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  obs(refresh)
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  observable.has = function (valueOrObs) {
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    return !!~object.indexOf(valueOrObs)
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  }
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  return observable
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  function update () {
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    var currentValues = object.map(get)
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    var newValues = obs()
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    currentValues.filter(notIncluded, newValues).forEach(removeFrom, object)
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    newValues.filter(notIncluded, currentValues).forEach(addTo, object)
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  }
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  function refresh () {
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    update()
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    broadcast(object)
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  }
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}
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function get (value) {
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  return value
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}
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function notIncluded (value) {
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  return !~this.indexOf(value)
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}
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function removeFrom (item) {
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  var index = this.indexOf(item)
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  if (~index) {
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    this.splice(index, 1)
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  }
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}
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function addTo (item) {
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  this.push(item)
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}
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