Turbo Vision

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The IDE for Turbo Pascal developed in Turbo Vision

Turbo Vision ( TVision for short , TV under Insiders ) is a framework for creating application programs with a character-oriented user interface . From the first version, the framework was object-oriented and event-driven, and it also offered its users solid conventions for the program structure. These ranged from the prefabricated program flow of the main function down to the conventions for the choice of identifier: A large part of the Delphi conventions for source code design come from Turbo Vision, such as the capital T , which is placed in front of the type name, or lower-case 2 or 3-character prefixes in front of enumerators.


Turbo Vision was initially developed by Borland Inc. in order to be able to create the IDEs for Turbo Pascal and Turbo C for MS-DOS on its basis . From the point of view of that time, it was important that it was strongly object-oriented and event-driven . The control flow is therefore not primarily understandable based on the instructions of the main program, but requires insight into the specific implementation of classes. Basically, the keyboard and mouse were equally designed as input devices, which was by no means a matter of course under DOS at the time.

With Turbo Pascal 6.0 (or Turbo C 2.0), Turbo Vision became available for users of Borland IDEs to develop their own applications. Not only was context-sensitive online help included, the concept of application development under Turbo Vision was also explained in detail and in an understandable manner.

After application development expanded increasingly to platforms that provided basic graphical possibilities for GUI programming, the importance of text-based systems declined. Turbo Vision and similar frameworks could only hold up for a few systems with extraordinary demands on computing power.

The source code of Turbo Vision was released into the public domain by Borland around 1997 together with the sources of the C ++ IDE .

Since then, the framework has been further developed under a BSD license for a large number of operating systems.

During the transition to Windows development, Borland developed a new framework for Borland Delphi , the Visual Component Library (VCL), after initial attempts with TPW (Turbo Pascal for Windows), which was closely linked to the concepts of TV , which, thanks to closures, was a major weakness from TV: to be able to control the behavior of components almost exclusively by deriving base classes .

Classic example

A program could already be created in the 1990s with the following few lines:

program MyTVApp;

uses App;

var MyApp: TApplication;


However, this program had nothing to offer that deviated from the standard. It had a menu bar with an exit option ( key combination Alt + x) and could be controlled with the mouse. The menu could be accessed F10via. In order to actually design your own programs, you had to derive at least one class from TApplication. So z. For example, you can add your own functions to the menu by overwriting the init method. In any case, Turbo Vision was forced to derive its own classes from standard classes.

Web links

Individual evidence

  1. Tvision "What about copyrights? [...] According to a FAQ entry in the Borland's site (was in http://www.inprise.com/devsupport/bcppbuilder/faq/QNA906.html  ( page no longer available , search in web archivesInfo: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. when I saw it) the code is public domain. I also asked in the Borland's newsgroup and the TeamB people (not official people but they are who give technical support in the net) said me the FAQ was right. "@1@ 2Template: Dead Link / www.inprise.com  
  2. Turbo Vision - by Borland Developer Support Staff ( Memento from January 19, 2004 in the Internet Archive ) on community.borland.com/ "Question: Where can I find the public domain version of Turbo Vision? Answer: It can be found at ftp .inprise.com / pub / borlandcpp / devsupport / archive / turbovision / " (1998, archived)