Are @{$list_ref} and @$list_ref equivalent in Perl?
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18-09-2019 - |
Question
I am new to Perl and am curious whether @{$list_ref}
and @$list_ref
are perfectly equivalent.
They seem to be interchangeable, but I am nervous that there is something subtle going on that I may be missing.
Solution
Yes, they're equivalent. You need braces when the expression is more than a simple scalar variable, e.g.,
push @{ $foo{$bar} } => "baz";
For more detail, see the Using References section of the documentation on references. The standard Perl documentation also includes several tutorials on using references:
- Understand References Today (mentioned by hobbs in the question's comments)
- Manipulating Arrays of Arrays in Perl
- Perl Data Structures Cookbook
OTHER TIPS
I've always found it helpful to remember that the outer braces are not syntactical magic, they're just a block that returns a reference. The expression inside the block can be anything that returns a reference:
$ perl -le 'sub foo {[qw/ apple orange banana /]} print ${print "Do something here."; foo()} [1]'
Do something here.
orange
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