The C23 edition of Modern C is now available for free

Re:The C23 edition of Modern C is now available for free by trealira on Tuesday October 15, 2024 @08:54PM (#41854621)

They can be useful when adding things to an array in a loop. A trivial example which removes a character from a null terminated string:

  void remove_char(char *s, char c) {
    size_t i, j;

    for (i = j = 0; s[i] != '\0'; i++)
      if (s[i] != c)
        s[j++] = c;
    s[j] = '\0';
  }

This might be better expressed with a higher order filter function, but C is too low level for things like that.

There are also idioms for stack manipulation using them: "stack[sp++] = pushed" and "popped = stack[--sp]".

C code does a lot of incrementing and decrementing by one, and so having dedicated syntax for it is convenient.

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Re:The C23 edition of Modern C is now available for free by jancsika on Wednesday October 16, 2024 @01:26AM (#41855882)

Note that in your example there appear to be three distinct meanings:

1. prefix incr/decr precedence: "stack[--sp]"

2. postfix incr/decr precedence: "s[j++]"

3. i have no particular preference for the precedence and am just using a shorthand I inherited from my ancestors whose use cases are no longer relevant to me: "i++" in your for loop

My rank speculation is that C programmers get in a habit of #3 and then forget to consider precedence in an expression where it matters.

In any case, it would be interesting to do a scan of github to see how often prefix and suffix incr/decr had to get switched up in a bugfix patch.

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Re:The C23 edition of Modern C is now available for free by trealira on Thursday October 24, 2024 @08:42PM (#41941250)

Silly mistake: that should read "s[j++] = s[i]".

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