solution for problem #6

categories/99-problems/P06-sdondley.pl

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+use v6;
+
+=begin pod
+
+=TITLE P06 - Find out whether a list is a palindrome.
+
+=AUTHOR Steve Dondley
+
+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>.
+
+=head1 What's interesting here?
+
+The subroutine does a comparison between the passed array and the reversed
+array using the C<eqv> operator. For the comparsion to work, both sides must be
+the have the same object types. In this case, we are comparing C<Seq> objects.
+
+The C<.flat> method is applied to the original array to return a Seq object
+which gets compared to the Seq object returned by C<.reverse> method.
+
+=head2 Features used
+
+=item C<eqv> - L<https://docs.raku.org/routine/eqv|infix eqv>
+=item C<flat> - L<https://docs.raku.org/routine/reverse|routine flat>
+=item C<reverse> - L<https://docs.raku.org/routine/reverse|routine reverse>
+
+=end pod
+
+sub is-palindrome(*@list) {
+    @list.flat eqv @list.reverse;
+}
+
+say is-palindrome(<1 2 1>); # yup
+say is-palindrome(<1 2 3>); # nope
+
+# vim: expandtab shiftwidth=4 ft=perl6