git ssb

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var resolve = require('./resolve')
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var isObservable = require('./is-observable')
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var onceIdle = require('./once-idle')
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module.exports = watchAll
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function watchAll (observables, listener, opts) {
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  if (!Array.isArray(observables)) {
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    observables = [ observables ]
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  }
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  var broadcasting = false
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  var releases = observables.map(bind, broadcast)
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  broadcast()
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  return function () {
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    releases.forEach(tryInvoke)
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    releases.length = 0
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  }
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  function broadcast () {
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    if (opts && opts.idle) {
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      if (!broadcasting) {
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        broadcasting = true
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        onceIdle(broadcastNow)
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      }
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    } else if (opts && opts.nextTick) {
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      if (!broadcasting) {
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        broadcasting = true
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        setImmediate(broadcastNow)
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      }
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    } else {
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      broadcastNow()
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    }
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  }
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  function broadcastNow () {
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    broadcasting = false
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    listener.apply(this, observables.map(resolve))
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  }
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}
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function bind (value) {
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  if (isObservable(value)) {
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    return value(this)
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  }
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}
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function tryInvoke (value) {
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  if (typeof value === 'function') {
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    return value()
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  }
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}
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