SVG games written using XQuery Update Facility

[hfmanson]

SVG games using XQUF

I have implemented a XQUF game engine. Starting with an SVG template, it loads and XML level e.g. chainlevel1.xml and using an XQUF query load_xq it appends the level to the SVG. The second argument to game.game is an object, keys is are event types e.g. click and the values are XQUF query to be executed when an event is triggered.

import * as game from './game';

const
    load_xq = <xquf query>
    , click_xq = <xquf query>
    , level = "chain-level" + game.getQueryVariable("level", "1") + ".xml"
    ;

game.game(
    level,
    load_xq,
    {
        click: click_xq
    }
);

The games are based on clickmaze's chainreaction and BoxUp games.

I created a pull request for this, is this the right way?

Is it possible to parse an xquery to a java object so the parsed xquery can be reused without re-evaluating the query string or xqueryx element?

I implemented these Xquery games earlier using my fork of declarative4all, where it's possible to use query as a new scripting language: example. Custom XQuery functions were added with xqib would this also be possible with fontoxpath?

looking forward for your comments.

[DrRataplan]

Hey!

I applaud the initiative but I doubt whether this library is the best place for it. Would you consider making your own repo, that we can even link to as a great example of integrating FontoXPath!

Some small feedback nonetheless

• I see you are using xml-js. Makes sense in a Node environment, but the browser already includes one! Just pass the 'application/xml` mime type to the window.DOMParser.
• I usually put XQuery files in separate files instead of inlining them in JavaScript. Makes it a lot easier to have some syntax highlighting in there.
• You are using the async version of evaluateUpdatingExpression. The sync one is exactly the same (fontoxpath is not async anyway, the async version was a mistake). It's just easier to stay in synchronous code
• I'd use async/await and fetch to get the level in. That should make the code a lot better readable.

Is it possible to parse an xquery to a java object so the parsed xquery can be reused without re-evaluating the query string or xqueryx element?

That actually already happens in the back: there is a map that caches the parsing (and static compilation result) of any XPath/XQuery object. You can just pass the same string and FontoXPath handles it for you!

I implemented these Xquery games earlier using my fork of declarative4all, where it's possible to use query as a new scripting language: example. Custom XQuery functions were added with xqib would this also be possible with fontoxpath?

Not familiar with XQIB I'm afraid. But if there is a will, there is a way. You could load FontoXPath, find all //script@type="application/xquery", see if it is a lib or a main module and execute them with the same rules as XQIB I think. Of course first define the functions XQIB defines. Could be a cool (separate) library using FontoXPath!

Kind regards,

Martin

[hfmanson]

Hello Martin,

• I removed xml-js and now explicitly state which members of the javascript event should be exported as XML attributes in an 'event' element
• now I am using an XQuery module using registerXQueryModule, the source of it is in <script id="xquery-module" type="application/xquery"> in the .xml files.
• switched to evaluateUpdatingExpressionSync
• created a separate repository