Very Horrible Question About Goto's

[Christian Tismer]

Michael Hudson wrote:
> 
> Michael Hudson <mwh21 at cam.ac.uk> writes:
> 
> > Gaetan Corneau <corg at copernic.com> writes:
> >
> > > I was surprised to learn that Python doesn't have a goto statement.
> > > Would it be difficult to add?
> >
> > No. The necessary opcodes are there (well, the one you need:
> > JUMP_ABSOLUTE).  You could use bytecodehacks to implement it, if you
> > liked...
> 
> Oh, hang on: the block stack would cause problems; how would you get
> 
> def f(x):
>     label: bob
>     for i in x:
>         if x:
>             goto: bob
> 
> to work? (by declaring it to be an error, I suppose).

This situation is exactly where continuations would
be superior than just a goto. The goto would jump
at bob's continuation, which simply does not have
this block.
But jumping from outside the block into the block
would also not work with continuations, unless
the block had a chance to start up before.

ciao - chris

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