RosettaCodeData/Task/Balanced-brackets/Raku/balanced-brackets-4.raku

grammar BalBrack { token TOP { '[' <TOP>* ']' } }

my $n = prompt "Number of bracket pairs: ";
my $s = ('[' xx $n, ']' xx $n).flat.pick(*).join;
say "$s { BalBrack.parse($s) ?? "is" !! "is not" } well-balanced";