Vad var projekt » Bauhaus«?

For a portion of the Newton's development cycle (roughly the middle third), the project's primary programming language was Dylan, a small, efficient object-oriented Lisp variant that still retains some interest. Although it was efficient (for its day, and considering its substantial run-time dynamism), Dylan was a tough sell for the large-format Newton (and for a development team unused to Lisp programming). With the move to the smaller form factor, Dylan was relegated to experimental status in the "Bauhaus Project" and eventually cancelled outright. Had it been retained, Dylan, with garbage collection and close OS integration, would have preceded Microsoft's managed code concept by over a decade.

Q: So, Bauhaus was written in Dylan?

Mikel: When I was working on Bauhaus [a Newton OS] (and before, on the first iteration of Newton OS) Dylan was even more a Lisp than it is now. It was called “Ralph”, and was basically Scheme+CLOS+a couple of ideas from other functional languages+a few things to please Smalltalk hackers at Apple. The development environment was a hacked version of MCL that supported two compilers and runtimes: (1) the Common Lisp Compiler and runtime, which ran on 68K hardware and targeted 68K hardware; and (2) the Ralph compiler and runtime, which ran on 68K hardware, but targeted ARM hardware (first on ribbon-cabled Newton prototype boards, and later on development prototypes of actual Newton hardware connected by means of Nubus inserts). There were lengthy meetings with the Apple Cambridge team that was designing Ralph and various interested fractions at Apple, arguing for their favorite language features. The strongest lobbyists were Lisp and Smalltalk programmers.

Q: What would have been the main differences of Bauhaus to the released Newton OS?

Mikel: Everything above the kernel was written in Dylan, except for 7 very low-level QuickDraw routines. Size in RAM was about twice the size of the C++ version. The UI was a littler richer and a little faster, and built in Dylan using a graphic system made by wrapping those 7 QuickDraw primitives in Dylan and building a graphical language on it.

It supported mobile software agents (but there was debate about how this could be made both robust and safe).

It had a means of automatically generated UI elements from READ-like forms with class specifications for the arguments; for example, there was a macro get-input-from-user that was like a binding form (like LET*) with class annotations; it dynamically constructed the UI to get the values for the bindings. It had nestable stylesheets for describing the appearance of UI elements (sort of like CSS for UI, but back when the Web was brand new and the W3C What's New page still listed all the websites in the world ).

It had a novel event-handling system capable of supporting arbitrary user-defined events. The event system identified events by pattern-matching.

It had a frame system used to implement a knowledge base that stored things like prototypical Person and Place and Date objects, and supported fuzzy comparisons. The so-called “IA” (“Intelligent Assistant”) subsytem used these frames so that it could guess things like the fact that when you write “Joe” you probably mean “Joseph Smith” or “Josephine Baker” from your address book. It was also used for the help system, so that it could guess that, for example, a sequence of actions was probably intended to establish a machine-to-machine connection and pop up information to help you do that, and for the event-handling system so that you could declaratively define new classes of high-level events and handlers for them.