Re: do { quit; } else { }

On 04/04/2025 20:23, Thiago Adams 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*/
   }
 

As a new language feature?
I think 'do {}' would be confused 'do {} while' (a parser - or a human - won't know this isn't a loop until the 'else' is seen. And then there's a possibility that that 'else' belongs to an 'if' but an omission or inclusion of a braces has screwed things up.
Perhaps a new keyword ('try' maybe) is better.
You'd also need to specify how nested do-else blocks will work. Or will 'quit' (so you have a new keyword anyway) only work at this level?
What about chained versions: do {} else do {} else ...; I guess 'quit' will just go to the next else block rather than quit the whole chain?
Note that this can be emulated in C now using:
    if
    {
      goto quit001;
    }
    else
    {quit001:
    }
Perhaps what C needs is a way to do that jump without an explicit goto:
    if
    {
      quit001;
    }
    else
    {quit001:
    }
You can require that such jumps can only go forwards.