c99/c++ localised variable definition

[Paul Richards]

On Tue, Feb 01, 2005 at 10:06:24AM -0800, John-Mark Gurney wrote:
> Paul Richards wrote this message on Mon, Jan 31, 2005 at 10:26 +0000:
> 
> [...]
> 
> > I think the loop usage though is one clear example where it is
> > clearer. I think there are others as well; where the usage of the
> > variable is clearly localised it is much easier to see a local
> > definition than to have to jump back and forth to find out what
> > variables are.
> 
> I personally think it isn't.  One thing that I do in python all to
> regularly (because it lacks variable declarations), is attempt to do:
> 	for i in foo:
> 		for j in bar:
> 			for i in baz:

That would work fine with c99.

> 
> And wonder why i gets such a strange value...  It appears that unless
> you have WARNS=4 set, warnings about:
> t.c:10: warning: declaration of 'i' shadows a previous local
> 
> don't show up.  So, I would say we HAVE to get the tree building with
> WARNS=4 and -Werror before we let this into style(9)...

The issue with shadowing outer scope variables is only an issue if
you need to access them. If your only using the syntax for loop
variables to do the looping then there's no issue.


-- 
Paul Richards