MS BASIC is widely considered to have been based on the internal structure of DEC BASIC.

▲ whartung 6 days ago | parent | next [-]

It may be widely considered, but that doesn't mean it's an accurate assertion.

The internal structure of DEC BASIC PLUS is a far, far cry from what MS-BASIC (MSB) is. Outside of some shared syntax, the implementations are night and day.

BASIC+ (B+) is compiled to p-code, not tokenized and then interpreted. Those are completely different runtime approaches. B+ has a raw text source that is edited and maintained by the runtime, MSB does not. After you hit ENTER on MSB, your "source code" is gone. It's converted, and not necessarily losslessly, into an internal tokenized form. That tokenized form is read and recreated into the source lines you see when you LIST the program.

This scratch text file for the B+ program actually allows B+ to work in even more memory starved environments than MSB because the text is never fully loaded into RAM, so the bulk of RAM is compiled byte codes and data. You also don't have to "pay" for having extra spaces in your code, as the raw text does not impact that actual runtime size in contrast to MSB tokenized form.

B+, being compiled, supported much different styles of things like loops and if statements.

  10 ODDSUM=ODDSUM + A(I) IF A(I) MOD 2 = 0 FOR I = 1 TO 10

MS-BASIC can not handle that properly with it tokenizer based system.

On the surface, they look similar with their interactive development environment. Internally, it was a completely different story.

▲ leoc 6 days ago | parent | prev [-]

Right, though there's two or three different questions here: whether DEC BASIC influenced MS BASIC, whether MS should have acknowledged that today, and whether DEC BASIC's influence on MS BASIC amounted to a copyright violation. On the last question, my guess would be that there's at least a reasonable argument that MS' use of the DEC BASIC code was transformative enough to get it off the hook, but IANAL. To the extent that it is in a grey area, honestly that's probably a good reason for MS to keep a diplomatic silence about any possible DEC influence today.

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reaperducer 6 days ago | parent [-]

there's two or three different questions here

Only if you weren't there.

You won't find the answers to everything online.

	▲	leoc 6 days ago \| parent [-]
		But that doesn't mean that there aren't two or three questions, just that there there are answers to which I, and most people here, aren't privy. And, sure, that wouldn't come as a suprise.