Has anybody any experience in using Gupta (formerly Centura) Team Developer?
If so, what do you think of it in terms of its capability to support the development of mature, scalable, maintainable applications?
Thanks
I have been using the CTD since version 1.1. Currently I'm still using 2.1 PTF4, mainly for doing rich client CRUDs under windows 98-Vista against Centura SQLBase, MS Sql Server or MS Access. I have not upgraded from 2.1 to the newer versions, so I can only talk about the relatively old 2.1 from 2001.(§)
Our applications typically have about 150 form windows, make heavy use of classes (still called "user defined variables" in 2.1) and integrate MS Office. We have no stability issues or memory leaks. The development environment is a bit long in the tooth, though: no intellisense, no smart debugging and practically unusable without a mouse. This may have changed with newer versions.
There is nothing in the nature of CTD that forces you to write un-maintainable code. Using classes and file-includes you can have a good degree of reusability in your code if you designed your code to be reusable, that is. A problem for maintainability may be that CTDs variables and classes do not have access modifiers like "private" or "protected". Also: no interfaces or abstract classes. On the other hand: multiple inheritance.
The "outline structure" of the code takes some getting used to, but I even sometimes miss the outline structure when I get lost in a sprawling C#-file with variable declarations and event handlers all over the place...
The controls for 2.1 where pretty complete but we still had to manually integrate "modern" things like toolbars, datepickers or tab-controls. OTOH it even has a numerical input field out of the box. One of the Unify-Newsletters stated that they added a lot of eye-candy, to let the apps look more up-to-date. The mtable-Extensions for table windows where very helpfull, available here: MTable by MICSTO . Integrating 3rd-party-DLLs (e.g. for integrating a smartcard-reader) is not really fun, especially when they use structs. Oh: and the "Centura Report Builder" is a royal pain in the derierre.
A big pro is the SDK that shipps with the CTD: this makes it very easy to integrate self written tools into the development environment, e.g. for code generation.
Bottom line: We used and still use CTD for scalable and maintainable apps. The learning curve can be a bit steep because of the unusual outline structure and can lead the unwary towards writing "ugly" code: e.g. lots of static functions, lots of code in the "Message Actions" and problems with variable scoping. I think your success with CTD will depend on the nature of the application you want to write: for a rich client CRUD you might almost certainly be better off than with .net, for a web app I honestly don't know.
Keep in mind that all this relates to the 8 year old 2.1 version of CTD. Things may be radically different now. If you can, get an evaluation version.
Edit: Aside from the pros and cons of the language alone, you might want to consider that CTD is a niche. There are not many free tools and I have yet to find a vibrant community (there was a newsgroup, but the server went down after the merger - maybe its still around somwhere). So, googling up help on specific Problems may no be easy.
(§) I did not continue the upgrade path from 2.1 to 5.1 because after the merge with Unify they wanted to make patches available only for subscribers to their support scheme (called GLS). Since I was not going to pay for bugfixes I deceided to continue using 2.1 for our legacy apps and switch to .net for new apps. I think they revised this later on.