Streamlined function to concatenate several input files into one output file

chomp.js

"use strict";
if (!require('streamline/module')(module)) return;

var fs = require('fs');
var streams = require('streamline/lib/streams/server/streams');

// cat ins > out
exports.chomp = function(ins, out, _) {
	streams.usingWritable(_, fs.createWriteStream(out), function(_, outStream) {
		for (var i = 0; i < ins.length; i++) {
			streams.usingReadable(_, fs.createReadStream(ins[i]), function(_, inStream) {
				streams.pump(_, inStream, outStream);
			});
		}
	});
}

// test it with cat *.js > out.txt
var names = fs.readdir(__dirname, _).filter(function(name) {
	return name.match(/.*\.js$/);
}).map(function(name) {
	return __dirname + '/' + name;
})

exports.chomp(names, __dirname + '/out.txt', _);

Added usingReadable, usingWritable and pump to the API, to capture common patterns and avoid proliferation of try/finally blocks in the code. Makes the code a bit leaner.