Acme.BookStore.HttpApi.Host/node_modules/lazystream/README.md
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# Lazy Streams
> *Create streams lazily when they are read from or written to.*
> `lazystream: 1.0.0` [](https://travis-ci.org/jpommerening/node-lazystream)
## Why?
Sometimes you feel the itch to open *all the files* at once. You want to pass a bunch of streams around, so the consumer does not need to worry where the data comes from.
From a software design point-of-view this sounds entirely reasonable. Then there is that neat little function `fs.createReadStream()` that opens a file and gives you a nice `fs.ReadStream` to pass around, so you use what the mighty creator deities of node bestowed upon you.
> `Error: EMFILE, too many open files`
> ─ *node*
This package provides two classes based on the node's Streams3 API (courtesy of `readable-stream` to ensure a stable version).
## Class: lazystream.Readable
A wrapper for readable streams. Extends [`stream.PassThrough`](http://nodejs.org/api/stream.html#stream_class_stream_passthrough).
### new lazystream.Readable(fn [, options])
* `fn` *{Function}*
The function that the lazy stream will call to obtain the stream to actually read from.
* `options` *{Object}*
Options for the underlying `PassThrough` stream, accessible by `fn`.
Creates a new readable stream. Once the stream is accessed (for example when you call its `read()` method, or attach a `data`-event listener) the `fn` function is called with the outer `lazystream.Readable` instance bound to `this`.
If you pass an `options` object to the constuctor, you can access it in your `fn` function.
```javascript
new lazystream.Readable(function (options) {
return fs.createReadStream('/dev/urandom');
});
```
## Class: lazystream.Writable
A wrapper for writable streams. Extends [`stream.PassThrough`](http://nodejs.org/api/stream.html#stream_class_stream_passthrough).
### new lazystream.Writable(fn [, options])
* `fn` *{Function}*
The function that the lazy stream will call to obtain the stream to actually write to.
* `options` *{Object}*
Options for the underlying `PassThrough` stream, accessible by `fn`.
Creates a new writable stream. Just like the one above but for writable streams.
```javascript
new lazystream.Writable(function () {
return fs.createWriteStream('/dev/null');
});
```
## Install
```console
$ npm install lazystream --save
lazystream@1.0.0 node_modules/lazystream
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