while (1)
        {
            FLAGS f;
            switch (*p)
            {
            case 'U':
            case 'u':
                f = FLAGS.unsigned;
                goto L1;
            case 'l':
                f = FLAGS.long_;
                error("lower case integer suffix 'l' is not allowed. Please use 'L' instead");
                goto L1;
            case 'L':
                f = FLAGS.long_;
            L1:
                p++;
                if ((flags & f) && !err)
                {
                    error("unrecognized token");
                    err = true;
                }
                flags = cast(FLAGS)(flags | f);
                continue;
            default:
                break;
            }
            break;
}


The last break statement prevents the loop from returned for a second iteration. Then why use a while ?

On Saturday, November 3, 2018 3:03:16 PM MDT Venkat via Digitalmars-d-learn wrote:
>          while (1)
>          {
>              FLAGS f;
>              switch (*p)
>              {
>              case 'U':
>              case 'u':
>                  f = FLAGS.unsigned;
>                  goto L1;
>              case 'l':
>                  f = FLAGS.long_;
>                  error("lower case integer suffix 'l' is not
> allowed. Please use 'L' instead");
>                  goto L1;
>              case 'L':
>                  f = FLAGS.long_;
>              L1:
>                  p++;
>                  if ((flags & f) && !err)
>                  {
>                      error("unrecognized token");
>                      err = true;
>                  }
>                  flags = cast(FLAGS)(flags | f);
>                  continue;
>              default:
>                  break;
>              }
>              break;
> }
>
>
> The last break statement prevents the loop from returned for a second iteration. Then why use a while ?

There's a continue right above the default case. So, if the code hits that point, it will loop back to the top.

- Jonathan M Davis

On Saturday, 3 November 2018 at 21:03:16 UTC, Venkat wrote:
> The last break statement prevents the loop from returned for a second iteration. Then why use a while ?

The continue statement may abort the current iteration and start the next, causing the final break to not necessarily be executed every iteration.

Thankyou.

As the great Gump's mother said, stupid is as stupid does.

On Saturday, 3 November 2018 at 21:13:49 UTC, Jonathan M Davis wrote:
> There's a continue right above the default case. So, if the code hits that point, it will loop back to the top.
>
> - Jonathan M Davis

There's also the benefit that FLAGS f exists only until the end of the loop, and thus won't be polluting the namespace later in the function.

Personally, when I want to make a block just for grouping code, I use if (true){} or static if (true){} depending on whether I want to it's variables go away afterwards.

IIRC, I could just use braces without any header intead of if (true){}, but the code block just isn't as easily distinquishable without anything at the top IMO.