merge-stream

Merge (interleave) a bunch of streams.

build status

Synopsis

```javascript var stream1 = new Stream(); var stream2 = new Stream();

var merged = mergeStream(stream1, stream2);

var stream3 = new Stream(); merged.add(stream3); merged.isEmpty(); //=> false ```

Description

This is adapted from event-stream separated into a new module, using Streams3.

API

mergeStream

Type: function

Merges an arbitrary number of streams. Returns a merged stream.

merged.add

A method to dynamically add more sources to the stream. The argument supplied to add can be either a source or an array of sources.

merged.isEmpty

A method that tells you if the merged stream is empty.

When a stream is "empty" (aka. no sources were added), it could not be returned to a gulp task.

So, we could do something like this:

js stream = require('merge-stream')(); // Something like a loop to add some streams to the merge stream // stream.add(streamA); // stream.add(streamB); return stream.isEmpty() ? null : stream;

Gulp example

An example use case for merge-stream is to combine parts of a task in a project's gulpfile.js like this:

```js const gulp = require('gulp'); const htmlValidator = require('gulp-w3c-html-validator'); const jsHint = require('gulp-jshint'); const mergeStream = require('merge-stream');

function lint() { return mergeStream( gulp.src('src/.html') .pipe(htmlValidator()) .pipe(htmlValidator.reporter()), gulp.src('src/.js') .pipe(jsHint()) .pipe(jsHint.reporter()) ); } gulp.task('lint', lint); ```

License

MIT