The VT100 Emulator aka Landing-Page for the Kibu Hackathon

This project is the official landing-page of the Kibu Hackathon series. It contains a VT100 emulator, with several small applications, even hidden ones. It is a Free and Open Source software, and we highly encourage you, to fork it, experiment with it, and commit back your changes!

Table of Content

• Writing an Application
• Standard Functions
• Visit Page
• Development

Writing an Application

The system can be easily extended with "programs". A program in this emulation is a simple Object, containing a main function, and optionally can have a desc (description) string and a man (manual) function to provide more information to the user, about what it does and how it does that.

The project uses a single global variable, called g, which is an Object. It is a good idea, to start your source file as follows:

var g = g || {};

To avoid polluting the global-namespace it is also a best practice to put the definition of the program inside a closure. After everything has been implemented, you should install the program, by calling the g.install function, which requires 4 arguments:

• name: (String) the name of the program,
• program: (Function) the program Object,
• aliases: (optional, Array) if the user can refer to this program by other name(s),
• hidden: (optional, Boolean) if the program should be hidden from help

(function ()
{
    'use strict';

    var NAME = 'example',
        DESC = 'My example program';

    /* Information to the user */
    function man(std)
    {
        std.io.writeLine(NAME);
        std.io.writeLine('  ' + DESC);
    }

    /* Single entry point */
    function main(std, argv)
    {
        // The implementation of the program goes here
    }

    /* Install program */
    g.install(NAME,
              {main : main,
               man  : man,
               desc : DESC},
              ['sample', 'test', 'myprog'],
              true);

})();

To make it work, the program has to be included in the head section of the index.html, right after the js/bin.js script. (Otherwise the g.install function won't work.)

Standard Functions

Both the man and the main functions take an Object called std as their first arguments. This Object has two sub-objects, io (Input/Output) and lib (library). The functions defined in the former one, can "manipulate the screen" (clear it, write or read from it), while the latter contains convenient utilities, such as handling the 'Yes/No' answers given to questions, or to open external links by requiring the user to click inside the screen.

The input/output functions:

• std.io.clear(): remove everything from the screen,
• std.io.write(String): write something on the screen,
• std.io.writeLine(String): write something on the screen and insert a new line after it,
• std.io.setReader(Function): set a function, which will process the user input. (The callback function takes two arguments, the std Object and the user's input String). If this function schedules another reader function, then it must return true

The library functions:

• std.lib.yesOrNo(String): if the string is a valid 'yes' it returns true; if it is a valid 'no' returns false; returns null otherwise,
• std.lib.invalidArg(String, String): prints the standard invalid argument error on the screen. Takes two aguments: the name of the command and the invalid option the user passed,
• std.lib.openPopUp(String): make the screen ready to be clicked on to redirect the user to another URL. It also prints the necessary messages to inform the user of this new functionality

Visit Page

Try it for yourself, by clicking here!

Development

The development of this project has only two minor dependencies, because these tools are called in the pre-commit hook of git, by a bash script.

• UglifyJS2 (node)
• JSHint (node)