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Comment by swatcoder | Hacker News Reader

Formally, yes, but in practice there's an enormous difference in the number and kind of records that might contain a comma and the number and kind that might contain a non-printable record seperator.

This difference carries over to C, where NULL got the job done for string termination pretty darn well, even if there were strong critiques to be weighed against it.

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I think the C example is meaningfully different. \0 in C is a string terminator. There is no more string after it, so you can just read the string "while (c != 0)", and there is never any need to escape it, because by definition strings cannot contain that character.

From a purely linguistic standpoint, the choice is sound. Obviously it's objectively a disaster but for unrelated reasons.

> the C example ... by definition strings cannot contain that character

They can, only some functions stop at the first zero:

    char s[] = "gogo\x00gogo";
    printf( "%d\n", (int)sizeof( s ) );

sizeof s (fun fact: you can omit the parentheses because it's not a function, it's an operator) reports the size of the array s, which is a variable of automatic storage duration.

Consider the following program:

  #include <stdio.h>
  #include <string.h>

  int main()
  {
      const char * const s = "gogo\x00gogo";
      const char t[] = "gogo\x00gogo";
      printf("%d,%d,%d,%d\n", 
          (int)sizeof s, 
          (int)strlen(s), // DO NOT EVER USE THIS FUNCTION
                          // YOU WILL BE FIRED IF YOU DO
          (int)sizeof t,
          (int)strlen(t)  // DO NOT EVER USE THIS FUNCTION
                          // YOU WILL BE FIRED IF YOU DO
      );
  }

  > 8,4,10,4

> > the C example ... by definition strings cannot contain that character

> They can, only some functions stop at the first zero:

> char s[] = "gogo\x00gogo";

And in what human language is that `\x00` a valid character? What rune/glyph/symbol represents it?

Nothing, you say? Well, looks like a good choice to me.

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