Re: hash of hashes and memory space...

Well, what's a variable to you?

Is each name a variable?
Well, there's only one name.
Is each block of allocated memory a variable?
$x has three given my $x = '123'; (SV head, SV body, string buffer).
%hash has 9 (-ish) given my %hash; $hash{'key'} = '123';.
my %hash; $hash{key}{subkey} = '123'; would have double minus two what my %hash; $hash{key} = '123'; has.
(Not counting any memory used by the pad or by the memory allocation system.)
Or are you constraining yourself to SVs and their derivatives (AV, HV, etc)?
$hash{key} = '123'; involves a hash (with a key and a number buckets) and a scalar.
$hash{key}{subkey} = '123'; involves two hashes (with a key and a number buckets each) and two scalars (one a reference, the other a string).

Your question doesn't make that much sense. What's your real question?

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Re^2: hash of hashes and memory space... by bcarroll (Pilgrim) on Mar 23, 2010 at 19:02 UTC
My question came about from looking at the output of a Data::Dumper and Data::Dump of a hash of hashes I am working with. Dumping the hash only prints the first hash key/value pairs not the under lining hashes or their key/value pairs. This made me think that a hash of hashes is not one single variable (container) but that each embedded hash is it's own separate container.	[reply]
Re^3: hash of hashes and memory space... by ikegami (Patriarch) on Mar 23, 2010 at 20:16 UTC
A "hash of hash" is really a "hash of references to hashes". `$h{foo}{bar} = 123;` [download] is short for `$h{foo}->{bar} = 123;` [download] and `${ $h{foo} }{bar} = 123;` [download] Something to try: `my %a; my %b; $a{foo} = \%b; $a{foo}{bar} = 123; print("$b{bar}\n");` [download]	[reply] [d/l] [select]
Re^3: hash of hashes and memory space... by jethro (Monsignor) on Mar 24, 2010 at 01:33 UTC
Strange. When I use Data::Dumper, I get all the subhashes shown too. Example: `#!/usr/bin/perl use warnings; use strict; use Data::Dumper; my %hash= ( 4, {3,4,5,6,7,8}); $hash{a}{b}{c}{d}{e}=366; print Dumper(\%hash); #output: $VAR1 = { '4' => { '3' => 4, '7' => 8, '5' => 6 }, 'a' => { 'b' => { 'c' => { 'd' => { 'e' => 366 } } } } };` [download] Maybe $Data::Dumper::Maxdepth is set to 1 in your script	[reply] [d/l]
Re^4: hash of hashes and memory space... by bcarroll (Pilgrim) on Mar 24, 2010 at 14:54 UTC
`print Dumper(\%hash);` You found my problem with Data::Dumper... I was using `print Dumper(%hash);` Thanks!	[reply] [d/l] [select]