dynamically referenced hashes ... editing

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

Hi monks,
I am creating dynamically generated hashes, as follows:

foreach my $name(@list_of_junk){
   %{$hash_ref} = (
    "junk_name" => "$name",
    "two" => result_of_function($name)
);
# %{$interface_hash_ref} = ("three" => "toilet"); (line deliberately commented out)
   push @interfaceref_array,    $interface_hash_ref;
   $interface_hash_ref = {};
};

Now what I'd like the commented-out line to do is add to the current hash via the reference $interface_hash_ref, but it doesn't seem to work. Any ideas why?
Cheers
Chris

Comment on dynamically referenced hashes ... editing

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Re: dynamically referenced hashes ... editing by kennethk (Abbot) on Jan 27, 2009 at 15:59 UTC
What you have written reinitializes your hash. What you mean to write is: `$interface_hash_ref->{"three"} = "toilet";` For more info, check out Perl References and Perl reference tutorial.	[reply] [d/l]
Re: dynamically referenced hashes ... editing by AnomalousMonk (Archbishop) on Jan 27, 2009 at 19:17 UTC
You are also, in what I assume is a typo, referencing two different hashes: `$hash_ref` and `$interface_hash_ref`. Per kennethk's reply, what you have might be more conscisely written (assuming `use warnings;` and `use strict;`) as: `my @interfaceref_array; for my $name (@list_of_junk) { my $hash_ref = { # curly brackets enclose junk_name => $name, # quotes not needed two => result_of_function($name), }; do_some_stuff(); $hash_ref->{three} = "toilet"; # quotes needed for value push @interfaceref_array, $hash_ref; }` [download] Or even as: `my @interfaceref_array; for my $name (@list_of_junk) { my %hash = ( # parentheses enclose junk_name => $name, two => result_of_function($name), ); do_some_stuff(); $hash{three} = "toilet"; push @interfaceref_array, \%hash; }` [download]	[reply] [d/l] [select]
Re^2: dynamically referenced hashes ... editing by chrishowe (Acolyte) on Jan 28, 2009 at 09:55 UTC
Excellent :-) It was a typo in the example, but not in the code, I tried to simplify it for ease of reading. Question answered anyway Cheers! Chris	[reply]