thunkify-wrap

Turn each node function in an object return a thunk. Turn a regular node function into one which returns a thunk, useful for generator-based flow control such as co.

Installation

npm install thunkify-wrap --save

Example

// the same as thunkify
var thunkify = require('thunkify-wrap');
var fs = require('fs');

fs.readFile = thunkify(fs.readFile);

fs.readFile('package.json', 'utf8')(function(err, str){

});

// thunkify an object
var user = {
  add: function () {},
  show: function () {},
  list: function () {}
}

module.exports = thunkify(user);
// module.exports = thunkify(user, ['add', 'show']);
// module.exports = thunkify(user, 'add');

genify

Wrap every function return a GeneratorFunction, that will be easy to write codes in only one way: yield* fn().

var genify = require('thunkify-wrap').genify;
var fs = require('fs');

fs.readFile = genify(fs.readFile);

var content = yield* fs.readFile(__filename, 'utf8');

event support

you can pass an event object, give end event name list, wrap event to thunk like this

var e = new EventEmitter();
var end = thunkify.event(e, 'finish');

yield end();
or
yield.end(['close', 'end']); // will cover `finish` event

when specified events emitted, this generator will go on. see more in the source code.

ctx

also you can pass ctx as contenxt into thunkify, and thunkify(object) will use object as the context by default.

var thunkify = require('thunkify-wrap');
var Cal = function (a, b) {
  this.a = a;
  this.b = b;
};

Cal.prototype.plus = function(callback) {
  var self = this;
  setTimeout(function () {
    callback(null, self.a + self.b);
  }, 5);
};

Cal.prototype.minus = function (callback) {
  var self = this;
  setTimeout(function () {
    callback(null, self.a - self.b);
  }, 5);
};

module.exports = Cal;

exports.create1 = function (a, b) {
  return thunkify(new Cal(a, b));
};

// or
exports.create2 = function (a, b) {
  var cal = new Cal(a, b);
  cal.plus = thunkify(cal.plus, cal);
  cal.minus = thunkify(cal.minus, cal);
};

methods

by pass methods list, support only thunkify a part of methods in an object.

exports.create3 = function (a, b) {
  var cal = new Cal(a, b);
  thunkify(cal, cal, ['plus']);
  // or
  thunkify(cal, ['plus']);
};

License

MIT