# $arg - user-supplied arg (think pthread_create)
# $once - unref body scalar during iteration
sub each_part {
- my ($self, $cb, $arg, $once) = @_;
+ my ($self, $cb, $arg, $once, $all) = @_;
my $p = mp_descend($self, $once // 0) or
- return $cb->([$self, 0, 0], $arg);
+ return $cb->([$self, 0, 1], $arg);
- $cb->([$self, 0, 0], $arg) if $self->{-call_cb}; # rare
+ $cb->([$self, 0, 0], $arg) if ($all || $self->{-call_cb}); # rare
$p = [ $p, 0 ];
my @s; # our virtual stack
(my $nxt = mp_descend($sub, $nr))) {
push(@s, $p) if scalar @{$p->[0]};
$p = [ $nxt, @idx, 0 ];
- $cb->([$sub, $depth, @idx], $arg) if $sub->{-call_cb};
+ ($all || $sub->{-call_cb}) and
+ $cb->([$sub, $depth, @idx], $arg);
} else { # a leaf node
$cb->([$sub, $depth, @idx], $arg);
}