Dumb newbie back in shell

[J. Clifford Dyer]

On Tue, Dec 11, 2007 at 08:36:54AM -0600, Chris Mellon wrote regarding Re: Dumb newbie back in shell:
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> Date: Tue, 11 Dec 2007 08:36:54 -0600
> From: "Chris Mellon" <arkanes at gmail.com>
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> Subject: Re: Dumb newbie back in shell
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> On Dec 11, 2007 8:23 AM, J. Clifford Dyer <jcd at sdf.lonestar.org> wrote:
> > The code you just posted doesn't compile successfully.
> >
> 
> It *compiles* fine, but it'll raise an error when run.
> 
> > However, in your code, you probably have char_ptr defined at the module level, and you're confused because you didn't declare it as global.  Am I right?  My crystal ball has a smudge on it, but I think I can still see okay.
> >
> 
> I assume that's what he think he's seeing also.
> 
> > You can still reference module level variables that aren't declared as global, but you can't assign to them.  Or rather, when you try to, you create a new local variable that shadows the global one.
> >
> 
> No, the determination of what names are local and which are global
> happens at compile time. The code as posted will not run correctly. It
> could run if it weren't in a function and were executed in global
> scope.
> 
> What's probably happening is that line_ptr < last_line is not true and
> the body of the function isn't executed at all. The unbound local
> exception is a runtime error that occurs when the local is accessed,
> not when the function is compiled.

Drat!  You're right.  I tried it in the interactive interpeter, and the function compiled just fine.  I tried calling the function and got an "UnboundLocalError."  I think I need to go sit in the corner and review the documentation.

Sorry all.  Disregard my previous post.

Chris, many thanks for your corrections.

Cheers,
Cliff