trequire

thunkify an entire module at once. Useful if you want to use normal, asynchronous modules with co. All newly created, thunkified functions are prefixed with "co"

Installation

$ npm install trequire

Examples

You can thunkify entire modules simply by using trequire in place of require:

var trequire = require('trequire');
var fs = trequire('fs');

fs.readFile('package.json', 'utf8', function(err, str){
  // normal async versions of all functions are still available
});

fs.coreadFile('package.json', 'utf8')(function(err, str){
  // all functions also have a thunkified version
});

This works on modules like fs which are just a collection of functions as well as on modules that construct and return objects (so long as those underlying objects can be accessed by recursively searching through the module). For example, you can easily create a thunkified redis client using trequire:

var trequire = require('trequire');
var redis = trequire('redis');
var rcli = redis.createClient()

rcli.set('foo', 'bar', function(err, res){
  // res = "OK"
});

rcli.coset('foo', 'bar')(function(err, res){
  // res = "OK"
});

rcli.get('foo', function(err, res){
  // res = "bar"
});

rcli.coget('foo')(function(err, res){
  // res = "bar"
});

trequire can also be called on objects. For example, to thunkify only the RedisClient instead of the entire module, you could do the following:

var trequire = require('trequire');
var redis = require('redis');

trequire(redis.RedisClient);

var rcli = redis.createClient();

// rcli now has coget, coset, etc.

Use with co

Thunks make it easy to write code that works well with the co module. This allows you to write code that is still asynchronous but in some cases is easier to read. co currently requires you to run your code with the --harmony flag as it utilizes javascript generators.

var trequire = require('trequire');
var redis = trequire('redis');
var co = require('co');

var rcli = redis.createClient();

co(function *(){
    
    // set the key "foo" to "bar"
    yield rcli.coset("foo","bar");

    // retrieve the value of the key "foo"
    var res = yield rcli.coget("foo");
    // res = "bar"

})()

For reference, this same code is repeated below in a standard asynchronous style:

var redis = require('redis');

var rcli = redis.createClient();

// set the key "foo" to "bar"
rcli.set("foo", "bar", function(err){

    // retrieve the value of the key "foo"
    rcli.get("foo", function(err, res){

        // res = "bar"

    })

})

By thunkifying existing modules and using co, you can leverage existing node modules while easily avoiding the common node pitfall of callback hell spaghetti code.

License

MIT