x.p6

sub share($p, $s) {
    supply {
        whenever $p {
            whenever $s {
                .emit;
            }
        }
    }.share
}

my $s = supply {
    "called".say;
    emit 1;
    die "I am die";
};  
$s = share(my $p = Promise.new, $s);    
$s.tap( -> $v { say "tap {$v}"; });  
react {  
    whenever $s { say $_; };
    $p.keep(1);
}