Specification:

P06 (*) Find out whether a list is a palindrome.
    A palindrome can be read forward or backward; e.g. <x a m a x>.

What's interesting here?

The subroutine does a comparison between the passed array and the reversed array using the eqv operator. For the comparsion to work, both sides must be the have the same object types. In this case, we are comparing Seq objects.

The .flat method is applied to the original array to return a Seq object which gets compared to the Seq object returned by .reverse method.

Features used

• eqv - https://docs.raku.org/routine/eqv

• flat - https://docs.raku.org/routine/reverse

• reverse - https://docs.raku.org/routine/reverse

sub is-palindrome(*@list) {
    @list.flat eqv @list.reverse;
}

say is-palindrome(<1 2 1>); # yup
say is-palindrome(<1 2 3>); # nope

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