How to remove duplicates items in list (Raku)

Question

FAQ: In Raku, how to remove duplicates from a list to only get unique values?

my $arr = [1, 2, 3, 2, 3, 1, 1, 0];
# desired output [1, 2, 3, 0]

Answer 1

1. Use The built-in unique

@arr.unique  # (1 2 3 0)

3. Use a Hash (alias map, dictionary)

my %unique = map {$_ => 1}, @arr;
%unique.keys;  # (0 1 2 3) do not rely on order

2. Use a Set: same method as before but in one line and optimized by the dev team

set(@arr).keys

• Links:
  • Answer on Roseta Code
  • Hash solution on Think Perl6
  • Same question for Perl, Python -> always same methods: a Hash or a Set