block scope?

Neal Becker ndbecker2 at gmail.com
Sat Apr 7 07:07:07 EDT 2007


James Stroud wrote:

> Paul Rubin wrote:
>> John Nagle <nagle at animats.com> writes:
>>>     In a language with few declarations, it's probably best not to
>>> have too many different nested scopes.  Python has a reasonable
>>> compromise in this area.  Functions and classes have a scope, but
>>> "if" and "for" do not.  That works adequately.
>> 
>> I think Perl did this pretty good.  If you say "my $i" that declares
>> $i to have block scope, and it's considered good practice to do this,
>> but it's not required.  You can say "for (my $i=0; $i < 5; $i++) { ... }"
>> and that gives $i the same scope as the for loop.  Come to think of it
>> you can do something similar in C++.
> 
> How then might one define a block? All lines at the same indent level
> and the lines nested within those lines?
> 
> i = 5
> for my i in xrange(4):
>    if i:             # skips first when i is 0
>      my i = 100
>      if i:
>        print i       # of course 100
>      break
>    print i           # i is between 0 & 3 here
> print i             # i is 5 here
> 
> 
> Doesn't leave a particularly bad taste in one's mouth, I guess (except
> for the intended abuse).
> 
> James

Yes, the above is pretty much what I had in mind.  +1.





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