basant307/AI_Governance_Project

1'use strict';2 3const { PassThrough } = require('stream');4 5module.exports = function (/*streams...*/) {6  var sources = []7  var output  = new PassThrough({objectMode: true})8 9  output.setMaxListeners(0)10 11  output.add = add12  output.isEmpty = isEmpty13 14  output.on('unpipe', remove)15 16  Array.prototype.slice.call(arguments).forEach(add)17 18  return output19 20  function add (source) {21    if (Array.isArray(source)) {22      source.forEach(add)23      return this24    }25 26    sources.push(source);27    source.once('end', remove.bind(null, source))28    source.once('error', output.emit.bind(output, 'error'))29    source.pipe(output, {end: false})30    return this31  }32 33  function isEmpty () {34    return sources.length == 0;35  }36 37  function remove (source) {38    sources = sources.filter(function (it) { return it !== source })39    if (!sources.length && output.readable) { output.end() }40  }41}42