This is the expected behavior. See 'autovivification' for more information. In
order to lookup $apples{crabapple}{weight}, $apples{crabapple} blooms into
existence. Chapter 8 in Programming Perl 3rd edition covers this in more detail.
You would have to check for the existence of $apples{$t}, then check for the
existence of $apples{$t}{weight} if that exists.
Quoting Joel Gwynn <[EMAIL PROTECTED]>:
> Wow. This is driving me crazy. I'm looking for a value in one of the
> keys in a hash, like so:
>
> my %apples = (macintosh => {weight => '10lb', cost => '5'},
> red_delicious => {weight => '15lb', cost => '2'},
> fuji => {weight => '12lb', cost => '7'});
>
> my @test = qw(granny_smith crabapple);
>
> foreach my $t (@test){ print "$t not found\n" unless $apples{$t}{weight}
> } print "\n-----------------------\n"; foreach my $a (keys %apples){
> print "$a: weight: $apples{$a}{weight}\n";
> }
>
> And what I get output is this:
>
> granny_smith not found
> crabapple not found
>
> -----------------------
> granny_smith: weight:
> fuji: weight: 12lb
> crabapple: weight:
> red_delicious: weight: 15lb
> macintosh: weight: 10lb
>
> Now, what's driving me crazy is that the two test values are being added
> to the hash, simply by looking for $apples{$t}{weight}. If I simply
> look for $apples{$t}, like so:
>
> foreach my $t (@test){ print "$t not found\n" unless $apples{$t} }
>
> new hash members are not created. Why should this be?
>
>
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