Hello MrSparks,

To make a hash slice, you need to use the braces (curly brackets) that normally go with hashes, not parentheses:

#! perl
use strict;
use warnings;
use diagnostics;

my %nationality_of = (
   'Ovid'          => 'Greek',
   'John Davidson' => 'Scottish',
   'Tennyson'      => 'English',
   'Poe'           => 'Tracky',    # Geek?
   );

my @nationalities = @nationality_of{ 'Ovid', 'Tennyson' };    # <-- Ch
+ange parentheses to braces here!
print "@nationalities";
[download]

Output:

16:03 >perl 1162_SoPW.pl
Greek English
16:03 >
[download]

@nationalities is in double quotes to force the behaviour provided by double-quote interpolation. See, for example, the entry for the $LIST_SEPARATOR variable (usually spelled $") in perlvar.¹

P.S. Please don’t include line numbers when posting code.²

Updates:
¹ With $" set to a space (the default), print "@nationalities"; is equivalent to print join(' ', @nationalities);.
² This makes it harder for monks to copy-and-paste the code and run it. If you want to see line numbers on code displayed in PerlMonks, add &001;: to the “Code Prefix” box in the “Code Listing Settings” section of your Display Settings.

Hope that helps,