Re: do { quit; } else { }

Em 4/4/2025 5:39 PM, Kaz Kylheku escreveu:

On 2025-04-04, Kaz Kylheku <643-408-1753@kylheku.com> wrote:

On 2025-04-04, Thiago Adams <thiago.adams@gmail.com> wrote:

    What do you think of this control block?
>
    do
    {
       FILE f = fopen("file.txt", "r");
>
       if (f == NULL) quit; /*goes to else part*/
>
       /*success here*/
       for (int i =0; i < 10; i++){
           ...
           if (error) quit;
       }
>
    }
    else
    {
       /*some error*/
    }

>
>
The else part might need access to some local variables
in the main part.
>
   do {
      char *name = calculate_path(PATH_PREFIX "/", name, ".txt");
      FILE *f = fopen(...)
>
      if (!f)
        quit;
      ...
   }
   else
   {
      printf("unable to open %s\n", name);
      ...
   }
>
If you make that work, you're creating scope wormholes between
disjoint curly braces, which is not allowed if youre name isn't
Bjarne Stroustrup.

 How about: do/else if/else if/else with argument passing to first
clause whose signature can take the argument list:
   do {
    ...
    quit("rage"); // goes to (char *arg)
    ...
    quit(42);     // goes to (int arg)
    ...
  }
  else if (char *arg)  // or just else? multiple elses on do, why not.
  {
  }
  else (int arg)
  {
  }
 Friday `f`noons, eh?
 

In this case.. I think try throw catch is suitable.
try{
   throw 1;
}
catch (int e){
}
try{
   throw;
}
catch {
}
but...the pattern I use is..
{
  int error = 0;
  try{
    error = ...
    if (error != 0) throw;
  }
  catch {
  }
  return error;
}