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Command

Usage

``javascript
var Command = require("command-pattern");

// What commands will do is up to you! But, first, they'll need a name...
var command = new Command("welcome");

command.implementation = function execute(/parameters..., /callback) {
// Here, this is the command itself.

callback(null, "Hello!");
};
`

$3


Surely, you can inherit from Command to craft your own commands:

`javascript
function WelcomeCommand() {
Command.call(this, "welcome");
}

inherit(WelcomeCommand, Command);

WelcomeCommand.prototype.implementation = function(/parameters.../) {
return "Hello!";
};
`

$3

When executed with a callback as the last parameter the command is considered to be asynchronous.
If it fails, it should invoke the callback with an error as the first parameter while while if it succeeds, the first parameter should be null`.
In any case, execution results should be passed in subsequent parameters.

$3

When executed without any callback the command is considered to be synchronous and should return the results immediately.
If it fails it should throw an error.

[npm-image]: https://img.shields.io/npm/v/command-pattern.svg?style=flat
[npm-url]: https://www.npmjs.com/package/command-pattern
[travis-image]: https://img.shields.io/travis/pvoisin/command-pattern.svg?branch=master
[travis-url]: https://travis-ci.org/pvoisin/command-pattern/
[coveralls-image]: https://coveralls.io/repos/pvoisin/command-pattern/badge.svg?branch=master
[coveralls-url]: https://coveralls.io/r/pvoisin/command-pattern?branch=master