Scaler of a hash, odd problem

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

I have a hash (which varies in size) and am using it in the following code.

foreach my $key (sort {$a cmp $b} keys %$hash) {
 if (scalar %{$$hash{$key}} > 2) {
  #do something
 }
 else {
  #do something else
 }
}
[download]

Which worked fine during my initial test cases. However, I just loaded a large sample of our real data into the system to run more tests and now I am getting the following error every 16th or 17th key:

Argument "2/8" isn't numeric in numeric gt (>)

sometimes the "2/8" is replaced by "1/8" .. and the error (warning?) repeats approximately 20 times (didn't count) before it continues.

No data is dropped/lost, it just displays that to stdout every 16th or 17th key.

what I am doing wrong?

Comment on Scaler of a hash, odd problem Download Code

Replies are listed 'Best First'.
Re: Scaler of a hash, odd problem by Elian (Parson) on Dec 12, 2002 at 16:47 UTC
Your code's broken. Hashes in scalar context don't return the number of keys in the hash, they return a bit of debugging info. If you want the number of entries in the hash, use `keys` in scalar context -- `scalar(keys %foo)` for example.	[reply] [d/l] [select]
Re: Re: Scaler of a hash, odd problem by Anonymous Monk on Dec 12, 2002 at 18:47 UTC
duh. thanks	[reply]
Re: Scaler of a hash, odd problem by fruiture (Curate) on Dec 12, 2002 at 16:53 UTC
A hash in scalar context returns such a string, as pointed out in perldata: "the number of used buckets and the number of allocated buckets" If you want the number of elements, use keys in scalar context. -- http://fruiture.de	[reply]