Re^3: uninitialized string variable

Yes, I am reasonably new to Perl, I am using Text::CSV::Slurp. The @ is used because $data is returned as a reference to an array of hashes, so:

@$data[0] -> {"data"}
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Returns the first hash inside data, and points to the value associated with the key "data". *unless my understanding is wrong*

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Re^4: uninitialized string variable by suhailck (Friar) on Aug 13, 2010 at 17:57 UTC
If $data is a reference to an AoH, then the following is sufficient `perl -le '$data=[{ data => 1 },{a => 2, b => 3}];print $$data[0]->{dat +a}' 1` [download] And if you try the below code, you can see the error u got, `perl -wle '$data=[{ data => 1 },{a => 2, b => 3}];print $$data[1]->{c +}' Use of uninitialized value in print at -e line 1.` [download] see perldsc for details.	[reply] [d/l] [select]
Re^5: uninitialized string variable by JavaFan (Canon) on Aug 13, 2010 at 18:17 UTC
`$ perl -wE '$data = [{"data" => "foo"}]; say @$data[0]->{"data"}' foo` [download] However, I would write that as `$$data[0]{"data"}` [download] which doesn't use an unneeded arrow, and uses the more usual dereference sigil. (I guess this case isn't caught by "Scalar value @... is better written as $...).	[reply] [d/l] [select]
Re^6: uninitialized string variable by choroba (Cardinal) on Aug 13, 2010 at 22:04 UTC
Isn't it the same as `$data->[0]{data}` I'd use?	[reply] [d/l]
Re^7: uninitialized string variable by jjw92 (Novice) on Aug 13, 2010 at 22:21 UTC
Re^7: uninitialized string variable by JavaFan (Canon) on Aug 14, 2010 at 07:40 UTC
Re^4: uninitialized string variable by JediWizard (Deacon) on Aug 14, 2010 at 02:38 UTC
This is only an opinion, but: I would rather keep to a single syntax for de-referencing when possible. As with most things in perl, there is more than one way to do it, and different ways have different strengths. In some cases using the `@$arrayref; %$hashref; $$scalarref` may be better, and in others `$arrayref->[0]; $hashref->{key};` may be better. That having been said... `@$data[$i]->{key}` uses two different syntax's for de-referecing, in the same statement. I'd say that `$data->[$i]{key}` is much clearer. They say that time changes things, but you actually have to change them yourself. —Andy Warhol	[reply] [d/l] [select]