Deskew Blog

I have been bitten for years whenever I have used precompiled headers with C++ platforms. It doesn’t matter what platform I’m using, they just never quite seem to work properly and reliably. From time to time you just get bizarre error messages that just don’t make any sense. So as a matter of course I just leave that option turned off and suffer the extra compilation time.

Recently, I’ve been working with Xcode 4 which we use for our Scorecerer iPad development. Precompiled headers are enabled by default and one of the first things I did was turn that option off and forgot about it.

However, one of my partners who also just switched to Xcode 4 did not turn off that option and guess what — he just got bitten. In his case, he built an update of the product with changes that I checked into our version control system. The code compiled and built perfectly but the Xcode IDE still displayed a bunch of those red error marker icons in various places and suggested that some classes and some variables were missing. Cleaning the project and rebuilding made no difference.

My partner futzed with it for an hour or so and then told me he was having the problem. I told him to turn off the precompiled headers option. He did that, did a clean followed by build and everything is fine.

So just turn off precompiled headers. You won’t be sorry.

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Object Pascal is a wonderful programming language! It is easy to read and understand while giving you a full array of modern object oriented language features. Strings are easy to work with, constructors are virtual, functions can be nested – these are only some of the goodies that come with the language.

I am by no means “religious” when it comes to languages though. It all depends on the project that one works on. The framework that one works with is much more important than the language itself in my opinion.

Object Pascal got popularized by the development environment called Delphi. It was initially created by Borland. If you programmed in the 80’s or early 90’s – chances are – you used Turbo Pascal (procedural Pascal) which was Borland’s best product at the time. They later evolved the idea of IDE into a modern language and framework.

Delphi’s strength was(still is), not only in basing itself on a great language – the VCL (Visual component Library) that came with the development environment was phenomenal. Moreover – it was extremely easy to develop your own components for repeated tasks and extend the IDE.

People who use Delphi will tell you that it is the best thing since sliced bread, but unfortunately – this was not enough to make Delphi or Object Pascal widely accepted. Delphi is still around and it is actively supported and developed by Embarcadero Technologies http://www.embarcadero.com/ . New versions work with .NET as well as windows native libraries.

An effort to bring Delphi to other platforms was made by Borland at some point. They called the product Kylix. It was a nice piece of software, but at that time – there was simply no market to sell the product to so the effort died.

Free Pascal is the open source implementation of Object Pascal. It is an actively developed, very modern language that runs on myriad of platforms and CPUs. If you have a device on your desk or your pocket – chances are – you can compile for that target using Free Pascal. It is a very mature project that started when Borland decided not to release Turbo Pascal 8 and focus solely on the windows platform (this later became the first version of Delphi). Since version 2.2 – Free Pascal supports Generics for example which are the equivalent of C++ Templates. Many other modern features are already built into the language.

Lazarus http://www.lazarus.freepascal.org/ is a free, open source IDE for Free Pascal. It is an effort to port the Delphi VCL to work with FPC and therefore on other platforms.

While the promise and potential of these tools was really appealing to us, the stability and maturity of Lazarus at the time of our evaluation was really not up to our standards. We could create and compile simple GUI applications and target different platforms, but the overall IDE was simply not usable in production environment.

While we would love to use Object Pascal in all our projects – there was simply no usable IDE for Free Pascal at the time and Embarcadero worked only on Windows. Free Pascal however is very mature, stable and full featured and we hope that Lazarus will catch up with it soon.

If you plan to develop a very simple application however – take a look at Lazarus and Free Pascal – it may be just the right toolset for you.

Next: Cross-platform desktop development options: .NET, Mono and Java

  
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