while (($_) = sort keys %data){ 
 
 print "while: $data{$_}\n"; 
 delete $data{$_}; 
}

[download]
This is a pretty expensive loop. You'd be much better doing: 
while (my ($k, $v) = each %data) {
  print "key is $k, value is $v\n";
}

[download]
Without those parens around $_, I would expect it to try to pass '5' into the block (which it would do) if you took away the sort function, but it doesn't do that. I suppose that might qualify as an insignificant bug.
No, sort in a scalar context always returns undef. Maybe someday, it'll return something useful. But not yet. No bug, except in perhaps your understanding. {grin}

-- Randal L. Schwartz, Perl hacker

In reply to Re: Re: While on hashes doesn't work? by merlyn
in thread While on hashes doesn't work? by blahblah

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