jecel

The original Smalltalk-72 focused on teaching children, but for Smalltalk-76 Alan Kay and Dan Ingalls wanted different things. Alan wanted to continue the kid focus while Dan argued that a language focused on advanced programmers could be used to implement a children's language on top of it. He was proven right decades later when EToys and then Scratch were implemented on top of Squeak Smalltalk, which closely followed Smalltalk-76.

This confusion frustrated me when I first read about Smalltalk in the August 1981 issue of Byte magazine. I couldn't figure it out and at that point I had learned several programming languages and none of them took me more than two hours to become reasonably fluent in. So I was having problems with a language that kids were using?!? Later on I found out about the differences between Smalltalk-72 and -80 and that the Byte articles explained things that made sense if you already knew them but didn't help you learn in the first place. All variations of Smalltalk have become my favorite way to program ever since.

Some prototype based languages use delegation instead of inheritance, so people assume that is the case for Self as well. The difference is subtle. But as you pointed out and Mario Wolczko said: "Self is like Smalltalk, only more so". There were also languages with neither inheritance nor delegation but that still included some scheme for sharing.

You are in luck: Alan Kay's original Smalltalk, also known as Smalltalk-72, doesn't have a syntax but instead allows you to define your own. Each class includes a single method that parses incoming messages however it wants.

The two problems with this were a lack of performance and the difficulty of understanding other people's code.

Dan Ingalls looked at the most popular styles people had created in Smalltalk-72 and defined a fixed syntax for Smalltalk-76 with the same flavor. This allowed him to "compile" -76 into bytecodes which would then be executed much faster by an interpreted virtual machine (and years later a JIT compiled one).

The analogy is putting grass everywhere in a new university campus and after a while seeing where the grass has been trampled and putting concrete sidewalks there.

For Smalltalk-80 they wanted people to be able to use it on their own computers and not only on the special Xerox PARC ones so the patched the syntax to use ASCII instead of their own character set. That made it uglier, in my opinion.

I can understand many people not liking the Smalltalk-80 syntax, but we do get some new people to the language every year and quite a few of them find the syntax one of the nicest features.

I think there were actually 68000 transistor positions. In the ROMs and PLAs not every potential transistor is populated but the missing ones were counted as well. But the number of actual transistors is only slightly smaller so it doesn't really matter.

One chip that could be used as a memory mapper for the 9900 (but wasn't in the TI99/4A) was the 74LS670, which was used in the IBM 5150 PC to allow the 8237 DMA chip to access more than 64KB (a limit that wasn't a problem when used in a 8080 system).

The naming of processor sizes is the subject of debate. I call a "pure 8 bit processor" one that has 8 bits for both data and addresses. Like the Kenbak-1. But these are so rare and educational rather than practical that it is very reasonable to call hybrid 8 bit / 16 bit processors just "8 bit".

This use of sloppy terms shouldn't make us forget that they are using an address extension trick, just like all those 16 bit processors that wanted to go beyond 64KB (for byte addressed such as the PDP-11, Z8000 or 8086) or 128KB (for word addressed, like the Xerox Alto's modified Data General Nova model).

Michael J. Flynn, best known in the computing world for his taxonomy of parallel computing (SISD, SIMD, MISD and MIMD), passed away on December 24, 2025

Two years after this booklet, the CRT memory it describes was replaced by core memory (becoming the first computer to use that technology).

Most people are not aware that after the failure of the PS/2 attempt to control the PC market, IBM tried a third time using 7 patents it had for the PC AT (they didn't have any on the original PC or the XT). In the first half of the 1990s they went after the chipset makers (mostly in Japan at that time) and in the second half of the 1990s they went after the PC makers themselves all around the world. The would threaten to sue for all machines made up to that point unless they licensed not only the 7 AT patents (which would expire in 2001) but also a bunch of other unrelated patents that were much newer. As far as I know everybody signed the deal, which meant that IBM could make money without actually making any PCs themselves.