calvinmetcalf · August 29, 2015 14:04
diff --git a/lazy_stream.js b/lazy_stream.js
 // In this example, I want to create a stream that pipes a file through a transform,
 // *without* beginning to read data from the file. I want the whole pipeline to be
 // lazy until I call read() on the end of the pipeline.
 // 
 // Instead, the console.log() call fires unexpectedly with every line of the file.

 var fs     = require('fs'),
    split  = require('split'),
    stream = require('stream');

 var dest = new stream.Transform({highWaterMark: 1});

 dest._transform = function(chunk, encoding, callback) {
  console.log(chunk); 
  callback(null, chunk);//<- need to emit something
 };

 var result = fs.createReadStream('./foo.txt').pipe(split()).pipe(dest);
	// In this example, I want to create a stream that pipes a file through a transform,
	// without beginning to read data from the file. I want the whole pipeline to be
	// lazy until I call read() on the end of the pipeline.
	//
	// Instead, the console.log() call fires unexpectedly with every line of the file.

	var fs = require('fs'),
	split = require('split'),
	stream = require('stream');

	var dest = new stream.Transform({highWaterMark: 1});

	dest._transform = function(chunk, encoding, callback) {
	console.log(chunk);
	callback(null, chunk);//<- need to emit something
	};

	var result = fs.createReadStream('./foo.txt').pipe(split()).pipe(dest);