Subroutine with arbitrary number of parameters

That would be the time to show how to define a subroutine that can get arbitrary number of values, but that requires introducing two concepts at a time. So I'll have to find a better set of examples.

Anyway, if we would like to implement a sum() subroutine that can get any number of values we need to define it like this:

#!/usr/bin/env perl6
use v6;

sub sum(*@values) {
    my $sum = 0;
    for @values -> $v {
        $sum += $v
    }
    return $sum;
}

say sum(2, 3);      # 5

my @a = (2, 3, 4);
my $z = 5;
say sum(@a, $z);  # 14

That is, we have to say that the expected parameter is a slurpy array. The * means it is slurpy, the @ still means it is an array. It will then accept any value as parameter and put them in the @values array.

So I can call it either with literal scalars or even with a list of arrays and scalars mixed

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