23 Jun
2023
23 Jun
'23
8:49 p.m.
I also stumbled over these language differences.
In my earlier compiler I tried to support all syntax that looked
reasonable, but now I tried to make the code more accurate to the actual
thing. I don't know much about the 6070 version of B and scj didn't
remember many technical details when I asked him about it a few years ago.
For auto vectors you can find an actual example here:
https://github.com/DoctorWkt/pdp7-unix/blob/master/src/cmd/ind.b#L3
Ken said that the language was the same on the pdp-7 and pdp-11. The
runtime we have for both are different but this must simply reflect
different evolutionary stages rather than platform differences.
I haven't gotten around to building my new compiler yet, but it would be
interesting to see if it's small enough to fit into the 4kw of pdp-7
userspace. The runtime would have to be updated and expanded of course.
In any case it should be fun to run it on v1/v2. Have to try that
on my 11/05 :)
It sure is interesting how many compilers have popped up for B over the
years. I also have a strangely strong love for this little language.
aap
On 23/06/23, Sebastien F4GRX wrote:
Hi again,
OK I found your compiler project on github: https://github.com/aap/b
I see you have introduced changes like this one:
- auto ab[500], ava[150];
- auto dirf, string, av, name[5], s;
+ auto ab 1000, ava 150;
+ auto dirf, string, av, name 5, s;
So it mean that at some point the auto declaration was changed?
Oh, yes it was. Here is the original syntax :
https://www.bell-labs.com/usr/dmr/www/kbman.html
And this one describes the use of quotes for auto arrays, but thats for
the H6070! https://www.bell-labs.com/usr/dmr/www/bref.pdf
Also in bref, auto a[4] reserves 5 words, but in ken's version auto a 4
reserves 4 words.
I think I will make a command line option to support both language specs :)
And fix my code, because I had found this example
https://github.com/Spydr06/BCause/blob/main/examples/fibonacci.b
and was convinced that constants in auto were initial values, but I now
understand that this is incorrect.
Initialized auto variables would have been an avoidable syntactic sugar
on these machines!