Object Pascal

Object Pascal
Paradigms	Imperative, structured, object-oriented, functional (Delphi dialect only), component-based, event-driven, generic
Family	Wirth Pascal
Designed by	Larry Tesler (Apple); Niklaus Wirth (for Apple); Anders Hejlsberg (Borland)
Developers	Apple Computer (initial); Borland International
First appeared	1986
Typing discipline	Static and dynamic (dynamic typing through variants, array of const, and RTTI), strong, safe
Scope	Lexical (static)
Platform	ARM, x86, PowerPC, ppc64, SPARC, MIPS, CLI, Java, Cocoa
Filename extensions	.p, .pp, .pas
Major implementations
	Delphi (x86, ARM), Free Pascal (x86, PowerPC, ppc64, SPARC, MIPS, ARM), Oxygene (CLI, Java, Native Cocoa), Smart Mobile Studio (JavaScript)
Dialects
	Apple, Turbo Pascal, Free Pascal (using objfpc or delphi mode), Delphi, Delphi.NET, Delphi Web Script, PascalABC.NET, Oxygene
Influenced by
	Pascal, Simula, Smalltalk
Influenced
	C#, Genie, Java, Nim, C/AL

Object Pascal is an extension to the programming language Pascal that provides object-oriented programming (OOP) features such as classes and methods.

The language was originally developed by Apple Computer as Clascal for the Lisa Workshop development system. As Lisa gave way to Macintosh, Apple collaborated with Niklaus Wirth, the author of Pascal, to develop an officially standardized version of Clascal. This was renamed Object Pascal. Through the mid-1980s, Object Pascal was the main programming language for early versions of the MacApp application framework. The language lost its place as the main development language on the Mac in 1991 with the release of the C++-based MacApp 3.0. Official support ended in 1996.

Symantec also developed a compiler for Object Pascal for their Think Pascal product, which could compile programs much faster than Apple's own Macintosh Programmer's Workshop (MPW). Symantec then developed the Think Class Library (TCL), based on MacApp concepts, which could be called from both Object Pascal and THINK C. The Think suite largely displaced MPW as the main development platform on the Mac in the late 1980s.

Symantec ported Object Pascal to the PC, and developed a similar object framework on that platform. In contrast to TCL, which eventually migrated to C++, the PC libraries remained mainly based on Pascal.

Borland added support for object-oriented programming to Turbo Pascal 5.5, which would eventually become the basis for the Object Pascal dialect used in Delphi created by Anders Hejlsberg. Delphi remained mainstream for business applications on the PC into the early 2000s, and was partly displaced in the 2000s with the introduction of the .NET Framework which included Hejlsberg's C#.

^ ^a ^b Gibson, Steve (May 8, 1989). "Borland and Microsoft Enter the Object-Oriented Pascal Ring". InfoWorld. Vol. 11, no. 19. p. 28. Archived from the original on February 29, 2024. Retrieved September 18, 2021.

[InfoworldTechTalk-1] Gibson, Steve (May 8, 1989). "Borland and Microsoft Enter the Object-Oriented Pascal Ring". InfoWorld. Vol. 11, no. 19. p. 28. Archived from the original on February 29, 2024. Retrieved September 18, 2021.

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