sampo5 days ago
FORTRAN II was a version of Fortran in use from 1958 to 1961, then superseded by FORTRAN IV. (IBM never published FORTRAN III, it was only an IBM internal project.)
fsckboy5 days ago
you buried the lede in the lead, where it links:
See also LISP 1.5
https://texdraft.github.io/lisp-1.5/listing.html
finally! being able to take the actual CAR and CDR!
aap_5 days ago
CAR here and CDR just below: https://texdraft.github.io/lisp-1.5/listing.html#line-7626
nyrikki5 days ago
For those not familiar with these old IBM machines that used decrementing of the index registers, this will help explain all the ??D instructions are there.
https://bitsavers.org/pdf/ibm/704/24-6661-2_704_Manual_1955....
Another lens for the FORTRAN case specifically, in the modern way we tend to say Fortran arrays are 'one' indexed, looking at this old code it is sometimes useful of thinking of it as a limit index, pulling from n-1 -> n. Or at least I found that useful for myself when digging into some of this a long time ago.
fsckboy5 days ago
thanks for finding that, i love it!
cide15 days ago
Its amazing to me how few instructions it took to write this. I would love to see higher level documentation of how it all fits together.
texdraftop5 days ago
You might like https://archive.computerhistory.org/resources/text/Fortran/1... and https://archive.computerhistory.org/resources/text/Fortran/1..., although they assume a good deal of familiarity with the machines the compiler ran on.
cide14 days ago
Thank you!