git ssb

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'use strict'
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//read a number of items and then stop.
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module.exports = function take (test, opts) {
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  opts = opts || {}
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  var last = opts.last || false // whether the first item for which !test(item) should still pass
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  var ended = false
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  if('number' === typeof test) {
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    last = true
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    var n = test; test = function () {
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      return --n
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    }
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  }
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  return function (read) {
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    function terminate (cb) {
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      read(true, function (err) {
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        last = false; cb(err || true)
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      })
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    }
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    return function (end, cb) {
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      if(ended)            last ? terminate(cb) : cb(ended)
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      else if(ended = end) read(ended, cb)
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      else
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        read(null, function (end, data) {
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          if(ended = ended || end) {
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            //last ? terminate(cb) :
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            cb(ended)
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          }
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          else if(!test(data)) {
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            ended = true
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            last ? cb(null, data) : terminate(cb)
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          }
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          else
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            cb(null, data)
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        })
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    }
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  }
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}
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