Virtual Pascal
Encyclopedia
Virtual Pascal is a free
32-bit Pascal compiler, IDE
, and debugger
for OS/2
and Microsoft Windows
, with some limited Linux
support. Although it had a wide user base in the late 1990s
, VP has not evolved significantly for several years, and the owner declared in 2005 that development had ceased. Virtual Pascal was developed by Vitaly Miryanov and later maintained by Allan Mertner.
, Borland Delphi
, and Free Pascal
, although language- and RTL-compatibility is limited for features introduced after Delphi v2 and FPC 1.0.x.
VP was primarily useful for the following purposes:
Significant features of Virtual Pascal include:
scene, probably because of its OS/2 port and being one of the few affordable multi-target compilers. Also Turbo Pascal
had been popular in the BBS scene too, but its successor, Delphi
was suddenly for Windows only. Virtual Pascal provided a migration path for existing codebases.
There has been pressure from some users for Virtual Pascal to be made into open-source software. This has not been done, provided the following reasoning:
Freeware
Freeware is computer software that is available for use at no cost or for an optional fee, but usually with one or more restricted usage rights. Freeware is in contrast to commercial software, which is typically sold for profit, but might be distributed for a business or commercial purpose in the...
32-bit Pascal compiler, IDE
Integrated development environment
An integrated development environment is a software application that provides comprehensive facilities to computer programmers for software development...
, and debugger
Debugger
A debugger or debugging tool is a computer program that is used to test and debug other programs . The code to be examined might alternatively be running on an instruction set simulator , a technique that allows great power in its ability to halt when specific conditions are encountered but which...
for OS/2
OS/2
OS/2 is a computer operating system, initially created by Microsoft and IBM, then later developed by IBM exclusively. The name stands for "Operating System/2," because it was introduced as part of the same generation change release as IBM's "Personal System/2 " line of second-generation personal...
and Microsoft Windows
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
, with some limited Linux
Linux
Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
support. Although it had a wide user base in the late 1990s
1990s
File:1990s decade montage.png|From left, clockwise: The Hubble Space Telescope floats in space after it was taken up in 1990; American F-16s and F-15s fly over burning oil fields and the USA Lexie in Operation Desert Storm, also known as the 1991 Gulf War; The signing of the Oslo Accords on...
, VP has not evolved significantly for several years, and the owner declared in 2005 that development had ceased. Virtual Pascal was developed by Vitaly Miryanov and later maintained by Allan Mertner.
Features
The compiler is compatible with Turbo PascalTurbo Pascal
Turbo Pascal is a software development system that includes a compiler and an integrated development environment for the Pascal programming language running on CP/M, CP/M-86, and DOS, developed by Borland under Philippe Kahn's leadership...
, Borland Delphi
Borland Delphi
Embarcadero Delphi is an integrated development environment for console, desktop graphical, web, and mobile applications.Delphi's compilers use its own Object Pascal dialect of Pascal and generate native code for 32- and 64-bit Windows operating systems, as well as 32-bit Mac OS X and iOS...
, and Free Pascal
Free Pascal
Free Pascal Compiler is a free Pascal and Object Pascal compiler.In addition to its own Object Pascal dialect, Free Pascal supports, to varying degrees, the dialects of several other compilers, including those of Turbo Pascal, Delphi, and some historical Macintosh compilers...
, although language- and RTL-compatibility is limited for features introduced after Delphi v2 and FPC 1.0.x.
VP was primarily useful for the following purposes:
- Easily port existing 16-bit Turbo PascalTurbo PascalTurbo Pascal is a software development system that includes a compiler and an integrated development environment for the Pascal programming language running on CP/M, CP/M-86, and DOS, developed by Borland under Philippe Kahn's leadership...
programs to 32 bits - Port existing 16-bit OWLObject Windows LibraryThe Object Windows Library is a Borland C++ object-oriented framework originally designed for WinAPI. It was used in Turbo Pascal for Windows, Borland Pascal and their Borland C++ package. It was a competitor to the Microsoft Foundation Class Library .OWL had incomplete support by the Borland C++...
programs to 32-bit Windows (in theory) - Write console (text-mode) programs for several platforms
- Pascal development using the 32-bit Windows APIWindows APIThe Windows API, informally WinAPI, is Microsoft's core set of application programming interfaces available in the Microsoft Windows operating systems. It was formerly called the Win32 API; however, the name "Windows API" more accurately reflects its roots in 16-bit Windows and its support on...
(the classic development, no COM!) - Learn object-oriented programmingObject-oriented programmingObject-oriented programming is a programming paradigm using "objects" – data structures consisting of data fields and methods together with their interactions – to design applications and computer programs. Programming techniques may include features such as data abstraction,...
Significant features of Virtual Pascal include:
- Text-mode IDE
- Debugger is integrated directly into the IDE and is reminiscent of Turbo DebuggerTurbo DebuggerTurbo Debugger was a machine-level debugger for MS-DOS executables, intended mainly for debugging Borland Turbo Pascal , and later Turbo C programs, sold by Borland...
- Fast compilation
- Tool-chain written mostly in Intel assembly
History
The compiler was quite popular in the BBSBulletin board system
A Bulletin Board System, or BBS, is a computer system running software that allows users to connect and log in to the system using a terminal program. Once logged in, a user can perform functions such as uploading and downloading software and data, reading news and bulletins, and exchanging...
scene, probably because of its OS/2 port and being one of the few affordable multi-target compilers. Also Turbo Pascal
Turbo Pascal
Turbo Pascal is a software development system that includes a compiler and an integrated development environment for the Pascal programming language running on CP/M, CP/M-86, and DOS, developed by Borland under Philippe Kahn's leadership...
had been popular in the BBS scene too, but its successor, Delphi
Delphi
Delphi is both an archaeological site and a modern town in Greece on the south-western spur of Mount Parnassus in the valley of Phocis.In Greek mythology, Delphi was the site of the Delphic oracle, the most important oracle in the classical Greek world, and a major site for the worship of the god...
was suddenly for Windows only. Virtual Pascal provided a migration path for existing codebases.
There has been pressure from some users for Virtual Pascal to be made into open-source software. This has not been done, provided the following reasoning:
- The compiler source is mostly written in Intel assembly which is hard to change and maintain.
- Part of the run-time library is proprietary to BorlandBorlandBorland Software Corporation is a software company first headquartered in Scotts Valley, California, Cupertino, California and finally Austin, Texas. It is now a Micro Focus subsidiary. It was founded in 1983 by Niels Jensen, Ole Henriksen, Mogens Glad and Philippe Kahn.-The 1980s:...
- Documentation and help are maintained with expensive proprietary tools
- There is nobody who fully understands the code. Alan said that some of the deeper areas were no-touch for him (original code by Vitaly)