You don't want to use a variable as a variable name. Dominus has said why much better than I can. Most likely, you want to use a hash to store the information about fruits:

my %fruits = {
    orange => { name => 'Malus',           size => 123 },
    apple  => { name => 'Citrus sinensis', size => 10 },
};
[download]

You can then access your data as

my $fruit = 'orange';
print $fruits{ $fruit }->{name}, "\n";
print $fruits{ $fruit }->{size};
[download]

Also see tye's References Quick Reference for how to use references.

Thanks, I did found a work around using a hash instead.

That's not a workaround, it's the preferred way to implement the behaviour you were initially looking for.

--
 David Serrano
 (Please treat my english text just like Perl code, i.e. feel free to notify me of any syntax, grammar, style and/or spelling error. Thank you!).

I am very confused how to use this tagging stuff

Update: Added last sentence.

Nothing to add to Corions answer, you don't want to use that. But if you still insist or are asking just out of curiosity, this works:

> perl -e '$size_orange=55; my $fruit = "orange"; my $name_var = "size
+_$fruit";print $$name_var; print $size,"\n";'
55
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Note that $size_orange has to be a global variable, it won't work when there is a 'my' before $size_orange. Instead of $$name_var ${$name_var} would also have worked, note the curly braces instead of your parentheses

Note that $size_orange has to be a global variable, it won't work when there is a 'my' before $size_orange.

Just a slight nitpick, $size_orange has to be a package variable.