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Re: Can I jump to a case inside a switch using goto?

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rivkaumiller@gmail.com writes:
[snip]
> In crux, the question is if I can use a switch-case's case-colon as a
> label for goto or not?
[snip]

No, you can't.  The target of a goto must be a the name of a label
defined with the "identifer ": syntax; a case label doesn't qualify.

You can always add labels as needed:

    switch (...) {
        case 0:
        L0:
            /* ... */
            break;
        case 1:
        L1:
            /* ... */
            break;
        /* ... */
        default:
        Default:
            /* ... */
            break;
    }
    /* ... */
    goto L1;
    goto L2;
    goto Default;

But I'd really advise you to rethink your design.  Careful use of goto
statements, usually to a pointer *later* in the code, can be useful for
error handling and for breaking out of nested loops, but heavy use of
gotos can easily result in spaghetti code.

If you're implementing a finite state machine, I suggest either a switch
statement in a loop, where the switch executes some chunk of code
depending on the current state, *or* a sequence of labelled blocks with
gotos.  (I personally prefer the former; for one thing, encoding the
current state in a variable rather than having it be implicit in the
current location in the program can be helpful).  Mixing case labels and
gotos could easily get out of control.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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Thread

Can I jump to a case inside a switch using goto? rivkaumiller@gmail.com - 2014-04-02 18:48 -0700
  Re: Can I jump to a case inside a switch using goto? Keith Thompson <kst-u@mib.org> - 2014-04-02 19:24 -0700
    Re: Can I jump to a case inside a switch using goto? <william@wilbur.25thandClement.com> - 2014-04-02 20:02 -0700
      Re: Can I jump to a case inside a switch using goto? rivkaumiller@gmail.com - 2014-04-02 23:04 -0700
        Re: Can I jump to a case inside a switch using goto? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-03 07:51 +0000
          Re: Can I jump to a case inside a switch using goto? "BartC" <bc@freeuk.com> - 2014-04-03 09:39 +0100
            Re: Can I jump to a case inside a switch using goto? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-03 11:52 +0100
              Re: Can I jump to a case inside a switch using goto? "BartC" <bc@freeuk.com> - 2014-04-03 12:42 +0100
                Re: Can I jump to a case inside a switch using goto? Keith Thompson <kst-u@mib.org> - 2014-04-03 08:04 -0700
                Re: Can I jump to a case inside a switch using goto? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-03 15:59 +0000
              Re: Can I jump to a case inside a switch using goto? Lowell Gilbert <lgusenet@be-well.ilk.org> - 2014-04-03 14:24 -0400
                Re: Can I jump to a case inside a switch using goto? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-04 23:06 +0100
          Re: Can I jump to a case inside a switch using goto? Paul N <gw7rib@aol.com> - 2014-04-03 04:15 -0700
            Computed GOTOs (Was: Can I jump to a case inside a switch using goto?) gazelle@shell.xmission.com (Kenny McCormack) - 2014-04-03 11:33 +0000
              Re: Computed GOTOs Richard <rgrdev_@gmail.com> - 2014-04-03 12:38 +0100
            Re: Can I jump to a case inside a switch using goto? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-04 23:22 +0100
        Re: Can I jump to a case inside a switch using goto? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-03 01:20 -0700
      Re: Can I jump to a case inside a switch using goto? rivkaumiller@gmail.com - 2014-04-03 14:51 -0700
      Re: Can I jump to a case inside a switch using goto? rivkaumiller@gmail.com - 2014-04-03 14:56 -0700
    Re: Can I jump to a case inside a switch using goto? rivkaumiller@gmail.com - 2014-04-02 23:08 -0700
      Re: Can I jump to a case inside a switch using goto? Keith Thompson <kst-u@mib.org> - 2014-04-03 08:09 -0700
    Re: Can I jump to a case inside a switch using goto? JohnF <john@please.see.sig.for.email.com> - 2014-04-03 06:36 +0000
      Re: Can I jump to a case inside a switch using goto? James Kuyper <jameskuyper@verizon.net> - 2014-04-03 07:48 -0400
        Re: Can I jump to a case inside a switch using goto? JohnF <john@please.see.sig.for.email.com> - 2014-04-03 12:21 +0000
          Re: Can I jump to a case inside a switch using goto? James Kuyper <jameskuyper@verizon.net> - 2014-04-03 10:16 -0400
            Re: Can I jump to a case inside a switch using goto? Keith Thompson <kst-u@mib.org> - 2014-04-03 08:12 -0700
              Re: Can I jump to a case inside a switch using goto? James Kuyper <jameskuyper@verizon.net> - 2014-04-03 12:44 -0400
            Re: Can I jump to a case inside a switch using goto? JohnF <john@please.see.sig.for.email.com> - 2014-04-04 07:06 +0000
            Re: Can I jump to a case inside a switch using goto? Tim Rentsch <txr@alumni.caltech.edu> - 2014-04-14 16:38 -0700
  Re: Can I jump to a case inside a switch using goto? rivkaumiller@gmail.com - 2014-04-03 00:18 -0700
  Re: Can I jump to a case inside a switch using goto? "BartC" <bc@freeuk.com> - 2014-04-03 09:49 +0100

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