Comments by "Lawrence D’Oliveiro" (@lawrencedoliveiro9104) on "ALGOL 68 Instead of Pascal? - Computerphile" video.

  1. 3:56 ALGOL 68 had its own terminology for so many things: types were called “modes”, addresses/pointers/references were called “names”, and instead of saying “input/output” or “I/O”, they coined the term “transput”.
    35
  2. A couple of significant notational differences between C and Pascal are, when declaring variables, C inherits the Algol syntax of type-spec before variable name: “«type-spec» «var-name»” whereas Pascal invented its own syntax: “«var-name» : «type-spec»”. And also pointer dereferencing: C uses a prefix operator “*«pointer-val»” whereas Pascal has a postfix one: “«pointer-val»^”. This may seem very tomayto-tomahto, but consider how C++, which inherits C syntax lock stock and barrel, is now trying to deal with newer features involving dependencies between types, for example between the arguments to a function and its result type. It now finds that, in addition to the C syntax of putting the return type before the function name, it also has to add an alternative syntax where the return type comes after the argument list, à la Pascal. As for the pointer issue, this may not occur very often, but back in my Mac programming days, more than once I had to write an expression like “thePort^^.theGDevice^^.gdPMap^^.pmTable”, which in C would have had to become “(**(**(**thePort).theGDevice).gdPMap).pmTable”. (These were structures defined for interfacing to the Mac system, not created by me.) Which would you prefer?
    27
  3. 1:40 I got hold of a copy of the ALGOL-68 spec when I started first year at Uni, and it just blew my mind. I was quite disappointed later to discover that most computer scientists considered Van Wijngaarden grammars to be just too complicated, and so they stuck to simpler, less formal, not to say cruder, ways of defining their languages.
    10
  4. I think they also introduced “overloading” for multiple definitions of an operator that were chosen according to context. That term is commonplace nowadays.
    8
  5. Pascal was such a (relatively) small language, there were loads of compilers available, including ones you had to pay for and ones that you got for free. ALGOL 68, on the other hand, was much larger and more complex, so in our little neck of the woods, we never saw a compiler for it.
    3
  6. ALGOL-W was also known as “Wirth-Hoare ALGOL”. Think of it as a prototype of ideas that Wirth would later embody in Pascal.
    3
  7. It wasn’t Apple’s fault for coming up with a situation that C cannot handle gracefully.
    3
  8. No, C++ and Python do not let you define new operators, they only let you overload existing ones. ALGOL 68 did allow you to come up with new operators. But you couldn’t use non-alphabetic/numeric characters for them.
    2
  9. “JOVIAL” = “Jules’ Own Version of the International Algorithmic Language”. That “International Algorithmic Language” being one of the names for ALGOL-58.
    2
  10. BCPL was really a kind of interim bootstrap language for implementing CPL (either “Combined Programming Language” or “Cambridge Plus London”, named for the two universities collaborating on the spec while each producing their own compiler). I can find very little detail online about the actual features of CPL. Think of it as an all-singing, all-dancing 1960s kitchen-sink programming language that would have gone up against PL/I, except with some slightly more advanced computer-science concepts behind it.
    1
  11. Sounds like they copied the idea from Burroughs.
    1
  12. Eclipsing binaries? Named for “al-gul”, aka “the demon”.
    1