However, that class doesn't have to have a 'new' method; and I'd argue that it's really superfluous, if the class's use cases are no more complex than this.

    return bless { name => $name, val => $val }, 'NameValTuple';
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The one potential downside of this is that it "exposes" the representation of the underlying object (in this case, a hash). Having a 'new' method hides all that. I personally believe that, at least in a simple case like this, there's hardly anything to be gained from hiding it.

You could inline new, but you still need name and val.

I don't see the point of changing

return NameValTuple->new( name => $name, val => $val );

{
   package NameValTuple;
   sub new  { my $class = shift; bless({ @_ }, $class) }
   sub name { $_[0]->{name} }
   sub val  { $_[0]->{val} }
}
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to

return bless { name => $name, val => $val }, 'NameValTuple';

{
   package NameValTuple;
   sub name { $_[0]->{name} }
   sub val  { $_[0]->{val} }
}
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It breaks encapsulation for no reason.

Hello dear Ikegami, hello dear people,

Dear Ikegami, bag your pardon, as I mitght possibly read wrong, you named different things. First time you wrote: Re: how to let sub return hash of 2 sub?

objectA.pm

sub parameter {
   ...
   return map { NameValTuple->new( name => $_, val => $rv{$_} } keys(%
+rv);
}
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But map if I'm thinking right returns an array, does'nt it? That is not 100% exactly what I need.

Second time you wrote: Re^3: how to let sub return hash of 2 sub?

sub parameter {
   ...
   return NameValTuple->new( name => $name, val => $val );
}
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.. which I am unsure what it does exactly. There are the 2 scalars $name and $val. But I think I need really two subs in the returned object.

Now as I see, you write the same as second time. Okay so far.

I have tried to guess, what you have meant to do. This is my solution with a little change at all.

package objectA;

sub new {
        my $class = shift;
        my $self  = {};
        bless $self, $class;
        return $self;
    }

sub map_query {

    my $self = shift;
    my $hash = shift;
    map { $self->{ values }->{ $_ } = $$hash{ $_ }; } keys %{ $hash };
}
    
sub parameter {
    my $self = shift;
    my $para = shift;

    print "__ parameter para[$para]    \n";
    my $param = $para =~ m/^([^\.]*\.)(.*?)$/i ? $2 : $para;
    print "__ parameter param[$param]    - val[$self->{ values }->{ $p
+ara }]\n";
    
    return NameValTuple->new( $param, $self->{ values }->{ $para } );
}

package NameValTuple;

sub new {
        my $class    = shift;
        my $self    = {
                        _key    => shift,
                        _val    => shift || '',
        };
        bless $self, $class;
        print ">> NameValTuple new key[$self->{_key}] val[$self->{_val
+}]\n";
        return $self;
    }

sub name {
    my $self  = shift;
    return $self->{_key};
}
sub val {
    my $self  = shift;
    return $self->{_val};
}

1;
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As you might have seen allready, I do not simple want the key and the value but have to change the key in this way, that instead of the key I have to return the key without the leading word plus dot.

This seams to work now, together with the former listed testpar.pl Re^2: how to let sub return hash of 2 sub?

Thanks to you all, Have A Nice Day, Thomas