Re: do { quit; } else { }

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?

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