[perl #124142] Something is off with multi dispatch, natives and where clauses

[Aleks-Daniel Jakimenko-Aleksejev via RT]

Still reproducible (2017.11, HEAD(5929887))

On 2015-03-22 05:17:48, moritz wrote:
> moritz@pat:~/p6/rakudo>cat ack.p6
> proto a(int, int) {*};
> multi a(int $ where 0, int \n) { n + 1 };
> multi a(int \m, int $ where 0) { a m -1 , 1 };
> multi a(int \m, int \n) {
> a m - 1, a m, n - 1
> };
> say a 3, 1
>
> moritz@pat:~/p6/rakudo>./perl6-m ack.p6
> Cannot call a(3, 1); none of these signatures match:
> (int $ where { ... }, int \n)
> (int \m, int $ where { ... })
> (int \m, int \n)
> in block <unit> at ack.p6:7
>
>
> When I replace every instance of 'int' with 'Int' in the test program,
> it works (no dispatch errors), and produces the output "13\n".