site_opytex/theme/node_modules/ordered-read-streams/index.js

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var Readable = require('stream').Readable;
var util = require('util');
function addStream(streams, stream)
{
if(!stream.readable) throw new Error('All input streams must be readable');
if(this._readableState.ended) throw new Error('Adding streams after ended');
var self = this;
stream._buffer = [];
stream.on('data', function(chunk)
{
if(this === streams[0])
self.push(chunk);
else
this._buffer.push(chunk);
});
stream.on('end', function()
{
for(var stream = streams[0];
stream && stream._readableState.ended;
stream = streams[0])
{
while(stream._buffer.length)
self.push(stream._buffer.shift());
streams.shift();
}
if(!streams.length) self.push(null);
});
stream.on('error', this.emit.bind(this, 'error'));
streams.push(stream);
}
function OrderedStreams(streams, options) {
if (!(this instanceof(OrderedStreams))) {
return new OrderedStreams(streams, options);
}
streams = streams || [];
options = options || {};
options.objectMode = true;
Readable.call(this, options);
if(!Array.isArray(streams)) streams = [streams];
if(!streams.length) return this.push(null); // no streams, close
var addStream_bind = addStream.bind(this, []);
this.concat = function()
{
Array.prototype.forEach.call(arguments, function(item)
{
if(Array.isArray(item))
item.forEach(addStream_bind);
else
addStream_bind(item);
});
};
this.concat(streams);
}
util.inherits(OrderedStreams, Readable);
OrderedStreams.prototype._read = function () {};
module.exports = OrderedStreams;