5 ms·

I dislike Modula-2's full upper-case reserved word syntax. I understand the reasoning behind it: to make language constructs consistent and stand out more, but

by sedatk 4y ago

I dislike Modula-2's full upper-case reserved word syntax. I understand the reasoning behind it: to make language constructs consistent and stand out more, but then, upper-case is harder to read. Make no mistake, I use that syntax when writing SQL, and it's very fitting there because the queries are short and I can't tolerate typos due to lack of a compilation step. But, in case of a compiled language, especially with the advent of syntax highlighting and edit-time analysis capabilities, I find it a nuisance.

mananaysiempre 4y ago
> [The reasoning behind] Modula-2's full upper-case reserved word syntax [is] to make language constructs consistent and stand out more I suspect it’s just inherited from ALGOL 68, where you were allowed to use names that coincide with language keywords at the cost of using one of a number of “stropping” conventions[1] to distinguish one from the other: surround each keyword with apostrophes (whence the term) or precede it with a period (if you’re using a single-case character set), type keywords in uppercase (if you’re not), or typeset them in bold (if you’re writing a paper—recall the original ALGOL problem statement was “like pseudocode from our papers but executable”). [1] https://en.wikipedia.org/wiki/Stropping_(syntax) https://en.wikipedia.org/wiki/Stropping_(syntax)
- sedatk 4y ago
  That might as well be the case, but Wirth did Pascal eight years before Modula-2, yet the former feels way more modern.
  - pjmlp 4y ago
    Not really, unless you're talking about Extended Pascal or the several dialects. ISO Pascal as Wirth originally designed it, only was modern in the sense of being much easier than ALGOL to implement and master, as learning language. Meanwhile Modula-2 was designed from the start to be a type safe systems programming language, based on Wirth's learnings with Mesa at Xerox PARC.
yarg 4y ago
> to make language constructs consistent and stand out more That sort of thing also makes parsing easier from the compiler side; you can look at the string token and know without context whether or not it's a keyword.
- FullyFunctional 4y ago
  Nope, compilers couldn't care less - it's much faster to hash keywords into the symbol table and just do a single lookup. The upper case is all about human readability. I suspect ALGOL's heavy reliance on named keywords (unlike C's more extensive use of symbols) relates to the inconsistencies of character sets etc at the time of the ALGOL's definition. IMvhO, Turbo Pascal (and Turbo Modula-2) would have been much nicer with a C-like (or Rust-like) syntax. Disclaimer: I worked professionally in Turbo Pascal for a few years.
  - int_19h 4y ago
    Algol (both 60 and 68) had various representations. The reference one, used in the spec, would use formatting to indicate things such as keywords, and used the conventional mathematic and engineering symbols where they were appropriate. Here's a bit of Algol-60 grammar: <arithmetic operator> ::= + | - | ⨉ | / | ÷ | ↑ <relational operator> ::= < | ≤ | = | ≥ | > | ≠ <logical operator> ::= ≡ | ⥰ | ∨ | ∧ | ¬ Most of these characters were not in contemporary character sets (although some later charsets would have symbols added specifically for Algol after it became more common). Given how much variation there was at the time, Algol designers didn't even try to solve that problem - they simply said that specific implementations of Algol would map the reference representation to some hardware-specific form, to be documented by the implementation. Those hardware representations would often use keywords for some of the operators.
    - hcs 4y ago
      Here's a table in a 1966 book showing the different keywords across implementations: https://archive.org/details/breuer-dictionary-for-computer-languages/page/n30/mode/1up https://archive.org/details/breuer-dictionary-for-computer-l... (It uses a weird glyph for NOT that I've never seen elsewhere, probably a limitation of typesetting.) Edit: Interesting to note that the English Electric KDF9's Algol used * at the beginning of all keywords, I suppose that's to simplify parsing, or maybe just to avoid reserving words.
int_19h 4y ago
Uppercase for keywords was a fairly common style at the time even in languages where they were case-insensitive (e.g. Pascal, BASIC, dBase). Which makes sense when you consider that syntax highlighting was still several years away, and it would take even longer for it to become widespread. Turbo Pascal wouldn't get syntax highlighting until version 7.0 - that's 1992!
- pjmlp 4y ago
  Turbo Pascal for Windows got it first.
malkia 4y ago
I could be completely wrong on this one, but Pascal not caring about case would've made it more available on machines where lower case was not available, but taken for other needs (like cyrillic). Not sure if it would've made difference (given the COCOM and Eastern Block), but my Apple ][ clone had cyrillic instead of lowercase letters... Or maybe my memory serves me wrong, and lower-case latin were not cyrillic, but somehow that's what I remember (was long time ago)...
- andrewshadura 4y ago
  Yes, that's called KOI-7.
  - malkia 4y ago
    Thank you so much, specifically I think I've had this on my Pravetz 8C (Apple ][/e clone) - https://en.wikipedia.org/wiki/KOI-7#KOI-7_N2 https://en.wikipedia.org/wiki/KOI-7#KOI-7_N2
silon42 4y ago
Personally, I don't use it even in SQL if I am starting from a clean slate...

by sedatk 4y ago

mananaysiempre 4y ago

> [The reasoning behind] Modula-2's full upper-case reserved word syntax [is] to make language constructs consistent and stand out more I suspect it’s just inherited from ALGOL 68, where you were allowed to use names that coincide with language keywords at the cost of using one of a number of “stropping” conventions[1] to distinguish one from the other: surround each keyword with apostrophes (whence the term) or precede it with a period (if you’re using a single-case character set), type keywords in uppercase (if you’re not), or typeset them in bold (if you’re writing a paper—recall the original ALGOL problem statement was “like pseudocode from our papers but executable”). [1] https://en.wikipedia.org/wiki/Stropping_(syntax) https://en.wikipedia.org/wiki/Stropping_(syntax)

sedatk 4y ago
That might as well be the case, but Wirth did Pascal eight years before Modula-2, yet the former feels way more modern.
- pjmlp 4y ago
  Not really, unless you're talking about Extended Pascal or the several dialects. ISO Pascal as Wirth originally designed it, only was modern in the sense of being much easier than ALGOL to implement and master, as learning language. Meanwhile Modula-2 was designed from the start to be a type safe systems programming language, based on Wirth's learnings with Mesa at Xerox PARC.

yarg 4y ago

> to make language constructs consistent and stand out more That sort of thing also makes parsing easier from the compiler side; you can look at the string token and know without context whether or not it's a keyword.

FullyFunctional 4y ago
Nope, compilers couldn't care less - it's much faster to hash keywords into the symbol table and just do a single lookup. The upper case is all about human readability. I suspect ALGOL's heavy reliance on named keywords (unlike C's more extensive use of symbols) relates to the inconsistencies of character sets etc at the time of the ALGOL's definition. IMvhO, Turbo Pascal (and Turbo Modula-2) would have been much nicer with a C-like (or Rust-like) syntax. Disclaimer: I worked professionally in Turbo Pascal for a few years.
- int_19h 4y ago
  Algol (both 60 and 68) had various representations. The reference one, used in the spec, would use formatting to indicate things such as keywords, and used the conventional mathematic and engineering symbols where they were appropriate. Here's a bit of Algol-60 grammar: <arithmetic operator> ::= + | - | ⨉ | / | ÷ | ↑ <relational operator> ::= < | ≤ | = | ≥ | > | ≠ <logical operator> ::= ≡ | ⥰ | ∨ | ∧ | ¬ Most of these characters were not in contemporary character sets (although some later charsets would have symbols added specifically for Algol after it became more common). Given how much variation there was at the time, Algol designers didn't even try to solve that problem - they simply said that specific implementations of Algol would map the reference representation to some hardware-specific form, to be documented by the implementation. Those hardware representations would often use keywords for some of the operators.
  - hcs 4y ago
    Here's a table in a 1966 book showing the different keywords across implementations: https://archive.org/details/breuer-dictionary-for-computer-languages/page/n30/mode/1up https://archive.org/details/breuer-dictionary-for-computer-l... (It uses a weird glyph for NOT that I've never seen elsewhere, probably a limitation of typesetting.) Edit: Interesting to note that the English Electric KDF9's Algol used * at the beginning of all keywords, I suppose that's to simplify parsing, or maybe just to avoid reserving words.

int_19h 4y ago

Uppercase for keywords was a fairly common style at the time even in languages where they were case-insensitive (e.g. Pascal, BASIC, dBase). Which makes sense when you consider that syntax highlighting was still several years away, and it would take even longer for it to become widespread. Turbo Pascal wouldn't get syntax highlighting until version 7.0 - that's 1992!

pjmlp 4y ago
Turbo Pascal for Windows got it first.

malkia 4y ago

I could be completely wrong on this one, but Pascal not caring about case would've made it more available on machines where lower case was not available, but taken for other needs (like cyrillic). Not sure if it would've made difference (given the COCOM and Eastern Block), but my Apple ][ clone had cyrillic instead of lowercase letters... Or maybe my memory serves me wrong, and lower-case latin were not cyrillic, but somehow that's what I remember (was long time ago)...

andrewshadura 4y ago
Yes, that's called KOI-7.
- malkia 4y ago
  Thank you so much, specifically I think I've had this on my Pravetz 8C (Apple ][/e clone) - https://en.wikipedia.org/wiki/KOI-7#KOI-7_N2 https://en.wikipedia.org/wiki/KOI-7#KOI-7_N2

silon42 4y ago

Personally, I don't use it even in SQL if I am starting from a clean slate...