MacApp

MacApp was Apple Computer's primary object oriented application framework for the classic Mac OS for much of the 1990s. First released in 1985, it is arguably the first such system to be widely used, notably on a microcomputer platform. Microsoft's MFC and Borland's OWL were both based directly on MacApp concepts.

It seems that Apple paid less attention to it than others, however, as it was alternately developed intensely and then ignored for long periods through the 1990s. Many Mac developers eventually gave up on it and moved to newer tools such as Metrowerks' PowerPlant and Symantec's Think Class Library (TCL). MacApp had a brief reprieve between 2000 and 2001, but after demoing a new version at WWDC in June 2001, all development was cancelled that October.

Even with this checkered career, MacApp was used for a variety of major applications, including Adobe Photoshop and SoftPress Freeway.

MacApp was a direct descendent of the Lisa Toolkit, Apple’s first effort in designing an object-oriented application framework. The MacApp and Lisa Toolkit projects were headed by Larry Tesler. The engineering team for the Toolkit and the initial implementation of MacApp included Larry Rosenstein, Scott Wallace, and Ken Doyle. MacApp was based on Object Pascal, Apple’s object-oriented extension to Pascal, developed in consultation with Pascal inventor Niklaus Wirth. At the time, Pascal was Apple's language of choice for Mac programming.

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