56 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			56 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
|  | # merge-stream
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|  | 
 | ||
|  | Merge (interleave) a bunch of streams. | ||
|  | 
 | ||
|  | [](http://travis-ci.org/grncdr/merge-stream) | ||
|  | 
 | ||
|  | ## 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](https://github.com/dominictarr/event-stream) separated into a new module, using Streams3. | ||
|  | 
 | ||
|  | ## API
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|  | 
 | ||
|  | ### `mergeStream`
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|  | 
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|  | Type: `function` | ||
|  | 
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|  | Merges an arbitrary number of streams. Returns a merged stream. | ||
|  | 
 | ||
|  | #### `merged.add`
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|  | 
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|  | 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`
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|  | 
 | ||
|  | 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; | ||
|  | ``` | ||
|  | 
 | ||
|  | ## License
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|  | 
 | ||
|  | MIT |