LisaPascal

> Not to mention they also demonstrated object-oriented programming Since 2023 we can study the source code of Lisa (see e.g. https://github.com/rochus-keller/lisapascal). Lisa’s system and applications were written mostly in Lisa Pascal (a compiled Pascal descendant) with some 68000 assembly; these compilers and their runtime bear no resemblance to the Smalltalk VM and bytecode system used on the Alto. The object‑oriented language Clascal was later created, as an "object‑oriented variant of Pascal", and used for the Lisa Toolkit; it later evolved into Object Pascal; both are statically compiled Algol‑family languages with Pascal syntax and a Simula‑style object model, not dynamically typed message‑sending systems like Smalltalk. Apple did not copy Smalltalk’s implementation or its language surface form for Lisa nor the Mac; there is bare

The new and relevant contribution is the "Apple Lisa Pascal Compiler sources", see the corresponding section and the link at the bottom of the page (http://pascal.hansotten.com/uploads/lisa/Lisa%20Pascal%20sou...). The "Apple Lisa Operating system sources" were already published in 2023 by the Computer History Museum (see also my code navigator, https://github.com/rochus-keller/lisapascal/).

Very interesting. Here are the two other videos in the series: https://www.youtube.com/watch?v=Qg0mHFcB510 Polaroids showing the Evolution of the Lisa GUI https://www.youtube.com/watch?v=NIJrCeRjZIU Bill Atkinson Interview for Lisa’s 40th Anniversary The videos were recorded in 2022, even before CHM published the source code. If you want to navigate the source code which Bill refers to in the video, here is a tool to do so: https://github.com/rochus-keller/LisaPascal.

Here is a tool to view, cross-reference and navigate the source code: https://github.com/rochus-keller/LisaPascal; Pascal, Clascal and assembler files are supported.

> As an illustrative example of this efficiency, I would like to cite https://github.com/rochus-keller/LisaPascal, where I was able to implement a parser and code browser within a week as a side project. With any other technology (including Smalltalk or Delphi) this would have taken months. As a former Smalltalk developer, what do you think about it would actually slow you down (despite popular claims re productivity in Smalltalk)? Is it tooling for C++ static types? If so, then what about Delphi? And is it one goal of yours, then, to mold Oberon+ so that it would eventually be at parity, productivity-wise, with C++?

C++, in the moderate subset e.g. also used in Qt 1 to 5, I still consider to be the optimal implementation language for a compiler and IDE at the present state of Oberon+ development, not because C++ is such a great language, but because of the ubiquitous availability and the huge, proven code base, which allows me to implement a project like Oberon+ as a single person worlds faster and more robust than with any other technology I know. As an illustrative example of this efficiency, I would like to cite https://github.com/rochus-keller/LisaPascal, where I was able to implement a parser and code browser within a week as a side project. With any other technology (including Smalltalk or Delphi) this would have taken months. A lot of development is still needed for Oberon+ to reach this point, and using the present approach I can support this

> Are Clascal, Lisa Pascal, and Object Pascal similar? Well, they are similar in any case since all are Pascal descendants and all are specifically descendants of Apple II and III Pascal. Clascal added OO features to Lisa Pascal - some new keywords and semantic rules; you can have a look at the grammar here https://github.com/rochus-keller/LisaPascal/blob/master/synt... where the Clascal additions are framed by ifdefs. Object Pascal had yet other keywords and semantics to achieve the same goal (e.g. "object" instead of "subclass", class name prefixes for methods instead of "methods of" blocks, etc. > how quickly Pascal and Object Pascal faded from use Lisa Pascal, Clascal and Object Pascal had some disadvantages to e.g. C++; there were e.g. no namespaces; whatever was imported with the "uses" clause shared the same global namespace. Apple

> the Office System applications were primarily written in the Clascal language This is not reflected in the source code released by the CHM. I analyzed the complete source code using https://github.com/rochus-keller/LisaPascal, but only found Clascal in 2 of 13 apps (APPW and APLP), and - besides the Lisa Toolkit library - only in 2 of 21 libraries (LIBPL and LIBQP); and only LIBQP (QuickPort) seems to depend on the Lisa Toolkit; everything else is directly using QuickDraw. So only a small fraction of the source code released by the CHM is Clascal; the primary language is Lisa Pascal. > Clascal language—an object-oriented dialect of Pascal designed by Apple with Niklaus Wirth No. Clascal was designed by Larry Tesler and team. What you refer to is Object Pascal, which was indeed a "co-design" between Apple and Prof. Wirth (ETH Zürich). Se

I just implemented a parser based on the Lisa Pascal 3 specification (see https://github.com/rochus-keller/LisaPascal) and started to analyze the published Lisa source code. So far I only saw two of the ~350 Lisa OS source files looking like Clascal (both from the Lisa toolkit). Lisa Pascal has quite a lot of essential features not present in original Pascal; an important one for system programming is the possibility to take the address of things which was not possible with original Pascal.