Course of Raku / Advanced / Containers / Contexts 🆕 / Exercises / Item or list

Solution: Item or list

Here is a possible solution to the task.

Code

my @a = 1, 2, 3;
my $count = 0;

my $x = $(@a);
$count++ for @($x);
say $count;

🦋 You can find the source code in the file item-or-list.raku.

Output

Comments

my $x = $(@a) forces item context, so the whole array is packed into the single scalar $x rather than spread out.
@($x) then forces list context, spreading $x back into its three elements. The for loop therefore runs three times, leaving the counter at 3. The two contextualisers are exact opposites: $( ) packs a list into one item, @( ) unpacks it again.

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