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Re: Computed GOTOs

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gazelle@shell.xmission.com (Kenny McCormack) writes:

> In article <d2d61fb2-b51f-498b-9a89-c230b7f55ff9@googlegroups.com>,
> Paul N  <gw7rib@aol.com> wrote:
> ...
>>In BCPL, labels were numbers just like any other variable. So you could do:
>>
>>GOTO val -> lab1 , lab2
>>
>>to choose one of two targets ( -> is the BCPL equivalent of ? : )
>>
>>or you could use an array; or you could even do
>>
>>GOTO lab + 4
>>
>>if jumping to slightly after a label is your idea of fun.
>
> Note, incidentally, that you *can* implement computed goto in C - in fact,
> in entirely standard (on topic) C.  The details of how to do it escape me
> at the moment, but it involves setjmp and longjmp.  Basically, you set up
> an array of jmpbufs and then longjmp to the one you want.  Somebody figured
> this out and explained it to me sometime back in the 80s.
>
> Perhaps someone here will take it on as a challenge...

Now you've done it.

-- 
"Avoid hyperbole at all costs, its the most destructive argument on
the planet" - Mark McIntyre in comp.lang.c

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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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