Feeds

Born Again Delphi

A word in CodeGear's shell-like

Eight steps to building an HP BladeSystem

So with all this talk about smart pointers, I guess you are agin garbage collection? OK, I admit it. Garbage collection is in general a great liberating thing. But I don't think it is right for native Delphi.

Delphi Object Pascal is surely supposed to be a 'as close to the metal as is sensible without being rust' sort of language. This is what differentiates it from C# and Java, which emphasise portability and safety, but run in vast, cosy-but-stifling, virtual machines that arrive (in one case) as gargantuan downloads and (in the other) seem to need updating every 10 minutes. When you do garbage collection, you are handing off a piece of control that by rights belongs to the obsessed, micro-optimising programmer. This is not the Delphi way.

Remember: we already got some Pascal garbage collection in Delphi.NET - and that didn't work out brilliantly, did it? Also, if we get GC in native New Delphi, will it not introduce hideous data sharing problems with Olde Delf modules, like managed and unmanaged code in Visual C++?

On the other hand, the smart pointer design I cited back there was the work of one Barry Kelly. Mr Kelly is one of the doubtless vast team that CodeGear has assembled to work on the compiler, and he seems to be pro garbage collection (and points out, amusingly, that Jeff 'Coding Horror' Atwood apparently believes that stack-allocated items are garbage-collected), although we cannot know what he thinks in this specific case.

Mr Kelly is rather well placed to have an opinion on this matter; if he were to produce it and it ran contrary to mine, I would be happy to consider it seriously. I am sure he is very relieved to hear that.

In real life, the issue of memory management does not arise as much as you'd expect in practical Delphi code, because of the ownership system in the VCL framework.

Ah yes - what about the VCL? Ok, not actually a compiler issue per se, but in Delphi the twain are intertwined.

The VCL was a miracle of its time. It was eight trillion times better than MFC. It got things right about delegation and event handling and resource storage and organisation that are still regularly being got wrong. The VCL hierarchy is perhaps a little deeper than is fashionable nowadays... but so what? The thing works, and works a treat.

But.

You will recall the design principle called 'separation of concerns', which says it is a good idea to minimise dependencies between different functions of your program. The VCL doesn't really 'do' separation of concerns. Its leanings are more towards consolidation of concerns into one honking big woe.

The solution to this, it seems to me, needn't be painful. The VCL is an excellent tool for implementing the 'V' part of the 'Model-View-Controller' pattern, and should be left alone.

All that is needed is a new, separate library to do the concern separating. And there is already an extremely elegant, compact and multi-lingual open source library called PureMVC. Although initially targeted at ActionScript and Flex, it already supports a dozen or so languages and platforms. I see no technical reason why New Object Pascal could not be added to the tally.

Among other advantages, it would mean that if CodeGear were to create a Delphi cross-compiler for, say, the Palm Pre, then they would not need to port the VCL at the same time (a highly desirable outcome in view of the Kylix and Delphi.NET fiascos, where many dollars were spent creating unsatisfactory re-implementations of the VCL). CodeGear could create a new front-end library specifically appropriate to the Pre device, and not backwards-compatible with anything, and they would be done.

Sure, users would have to rewrite the front-ends of their MVC structured programs - but realistically they would have to do that in any case, because a PC UI does not work well on a smartphone (don't believe me? Ask a Windows Mobile user). Everybody would be happy.

HP ProLiant Gen8: Integrated lifecycle automation

More from The Register

next story
Secure microkernel that uses maths to be 'bug free' goes open source
Hacker-repelling, drone-protecting code will soon be yours to tweak as you see fit
KDE releases ice-cream coloured Plasma 5 just in time for summer
Melty but refreshing - popular rival to Mint's Cinnamon's still a work in progress
NO MORE ALL CAPS and other pleasures of Visual Studio 14
Unpicking a packed preview that breaks down ASP.NET
Cheer up, Nokia fans. It can start making mobes again in 18 months
The real winner of the Nokia sale is *drumroll* ... Nokia
Put down that Oracle database patch: It could cost $23,000 per CPU
On-by-default INMEMORY tech a boon for developers ... as long as they can afford it
Another day, another Firefox: Version 31 is upon us ALREADY
Web devs, Mozilla really wants you to like this one
Google shows off new Chrome OS look
Athena springs full-grown from Chromium project's head
prev story

Whitepapers

Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Consolidation: The Foundation for IT Business Transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.
Application security programs and practises
Follow a few strategies and your organization can gain the full benefits of open source and the cloud without compromising the security of your applications.
How modern custom applications can spur business growth
Learn how to create, deploy and manage custom applications without consuming or expanding the need for scarce, expensive IT resources.
Securing Web Applications Made Simple and Scalable
Learn how automated security testing can provide a simple and scalable way to protect your web applications.