4 ms·

There are 3 things I find funny about that comment: ML didn’t have single-line comments, so same level of surprising limitation. I’ve never heard someone refer

by dahart 2y ago

There are 3 things I find funny about that comment: ML didn’t have single-line comments, so same level of surprising limitation. I’ve never heard someone refer to C as “expressive”, but maybe it was in 1972 when compared to assembly. And what bearing does the comment syntax have on the expressiveness of a language? I would argue absolutely none at all, by definition. :P

susam 2y ago
> ML didn’t have single-line comments, so same level of surprising limitation. It is not quite clear to me why the lack of single-line comments is such a surprising limitation. After all, a single-line block comment can easily serve as a substitute. However, there is no straightforward workaround for the lack of nested block comments. > I’ve never heard someone refer to C as “expressive”, but maybe it was in 1972 when compared to assembly. I was thinking of Fortran in this context. For instance, Fortran 77 lacked function pointers and offered a limited set of control flow structures, along with cumbersome support for recursion. I know Fortran, with its native support for multidimensional arrays, excelled in numerical and scientific computing but C quickly became the preferred language for general purpose computing. While very few today would consider C a pinnacle of expressiveness, when I was learning C, the landscape of mainstream programming languages was much more restricted. In fact, the preface to the first edition of K&R notes the following: "In our experience, C has proven to be a pleasant, expressive and versatile language for a wide variety of programs." C, Pascal, etc. stood out as some of the few mainstream programming languages that offered a reasonable level of expressiveness. Of course, Lisp was exceptionally expressive in its own right, but it wasn't always the best fit for certain applications or environments. > And what bearing does the comment syntax have on the expressiveness of a language? Nothing at all. I agree. The expressiveness of C comes from its grammar, which the language parser handles. Support for nested comments, in the context of C, is a concern for the lexer, so indeed one does not directly influence the other. However, it is still curious that a language with such a sophisticated grammar and parser could not allocate a bit of its complexity budget to support nested comments in its lexer. This is a trivial matter, I know, but I still couldn't help but wonder about it.
- dahart 2y ago
  Fair enough. From my perspective, lack of single line comments is a little surprising because most other languages had it at the time (1973, when ML was introduced). Lack of nested comments doesn’t seem surprising, because it isn’t an important feature for a language, and because most other languages did not have it at the time (1972, when C was introduced). I can imagine both pro and con arguments for supporting nested comments, but regardless of what I think, C certainly could have added support for nested comments at any time, and hasn’t, which suggests that there isn’t sufficient need for it. That might be the entire explanation: not even worth a little complexity.
  - masfuerte 2y ago
    AFAIK, C didn't get single line comments until C99. They were a C++ feature originally.
    - dahart 2y ago
      Oh wow, I didn’t remember that, and I did start writing C before 99. I stand corrected. I guess that is a little surprising. ;) Is true that many languages had single line comments? Maybe I’m forgetting more, but I remember everything else having single line comments… asm, basic, shell. I used Pascal in the 80s and apparently forgot it didn’t have line comments either?
      - masfuerte 2y ago
        That's my recollection, that most languages had single line comments. Some had multi-line comments but C++ is the first I remember having syntaxes for both. That said, I'm not terribly familiar with pre-80s stuff.
      - quietbritishjim 2y ago
        Some C compilers supported it as an unofficial extension well before C99, so that could be why you didn't realise or don't remember. I think that included both Visual Studio (which was really a C++ compiler that could turn off the C++ bits) and GCC with GNU extensions enabled.
michaelcampbell 2y ago
I was barely too young for this to make much of an impact at the time, (but older than many, perhaps most, here), I understand why C was considered a "high level language", but it still hits me weird, given today's context.

by dahart 2y ago

susam 2y ago

> ML didn’t have single-line comments, so same level of surprising limitation. It is not quite clear to me why the lack of single-line comments is such a surprising limitation. After all, a single-line block comment can easily serve as a substitute. However, there is no straightforward workaround for the lack of nested block comments. > I’ve never heard someone refer to C as “expressive”, but maybe it was in 1972 when compared to assembly. I was thinking of Fortran in this context. For instance, Fortran 77 lacked function pointers and offered a limited set of control flow structures, along with cumbersome support for recursion. I know Fortran, with its native support for multidimensional arrays, excelled in numerical and scientific computing but C quickly became the preferred language for general purpose computing. While very few today would consider C a pinnacle of expressiveness, when I was learning C, the landscape of mainstream programming languages was much more restricted. In fact, the preface to the first edition of K&R notes the following: "In our experience, C has proven to be a pleasant, expressive and versatile language for a wide variety of programs." C, Pascal, etc. stood out as some of the few mainstream programming languages that offered a reasonable level of expressiveness. Of course, Lisp was exceptionally expressive in its own right, but it wasn't always the best fit for certain applications or environments. > And what bearing does the comment syntax have on the expressiveness of a language? Nothing at all. I agree. The expressiveness of C comes from its grammar, which the language parser handles. Support for nested comments, in the context of C, is a concern for the lexer, so indeed one does not directly influence the other. However, it is still curious that a language with such a sophisticated grammar and parser could not allocate a bit of its complexity budget to support nested comments in its lexer. This is a trivial matter, I know, but I still couldn't help but wonder about it.

dahart 2y ago
Fair enough. From my perspective, lack of single line comments is a little surprising because most other languages had it at the time (1973, when ML was introduced). Lack of nested comments doesn’t seem surprising, because it isn’t an important feature for a language, and because most other languages did not have it at the time (1972, when C was introduced). I can imagine both pro and con arguments for supporting nested comments, but regardless of what I think, C certainly could have added support for nested comments at any time, and hasn’t, which suggests that there isn’t sufficient need for it. That might be the entire explanation: not even worth a little complexity.
- masfuerte 2y ago
  AFAIK, C didn't get single line comments until C99. They were a C++ feature originally.
  - dahart 2y ago
    Oh wow, I didn’t remember that, and I did start writing C before 99. I stand corrected. I guess that is a little surprising. ;) Is true that many languages had single line comments? Maybe I’m forgetting more, but I remember everything else having single line comments… asm, basic, shell. I used Pascal in the 80s and apparently forgot it didn’t have line comments either?
    - masfuerte 2y ago
      That's my recollection, that most languages had single line comments. Some had multi-line comments but C++ is the first I remember having syntaxes for both. That said, I'm not terribly familiar with pre-80s stuff.
    - quietbritishjim 2y ago
      Some C compilers supported it as an unofficial extension well before C99, so that could be why you didn't realise or don't remember. I think that included both Visual Studio (which was really a C++ compiler that could turn off the C++ bits) and GCC with GNU extensions enabled.

michaelcampbell 2y ago

I was barely too young for this to make much of an impact at the time, (but older than many, perhaps most, here), I understand why C was considered a "high level language", but it still hits me weird, given today's context.