Re^4: uninitialized string variable

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.

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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 `$$data[0]{"data"}` [download] which doesn't use an unneeded arrow, and uses the more usual dereference sigil. (I guess this case isn't caught by "Scalar value @... is better written as $...).	[reply] [d/l] [select]
Re^6: uninitialized string variable by choroba (Cardinal) on Aug 13, 2010 at 22:04 UTC
Isn't it the same as `$data->[0]{data}` I'd use?	[reply] [d/l]
Re^7: uninitialized string variable by JavaFan (Canon) on Aug 14, 2010 at 07:40 UTC
`$data->[0]{data}` and `$$data[0]{data}` are equivalent. And so is `$data->[0]->{data}`. Use whatever you prefer.	[reply] [d/l] [select]
Re^7: uninitialized string variable by jjw92 (Novice) on Aug 13, 2010 at 22:21 UTC
From what I have tried it is the same thing (if you put "data") That does look cleaner. I was just doing it the way I learned how to. I like the cleaned up look though. Thanks	[reply]