Re: oop, variable that counts the number of objects created

Just a random example using Zydeco...

use Zydeco prefix => 'App';

class Car {
    has name  ( type => Str );
    has price ( type => Num );
    has speed (
        type         => Num,
        default      => 0,
        handles_via  => 'Number',
        handles      => {
            speed_up    => 'add',
            slow_down   => 'sub',
        },
    );
    
    my $count;
    method BUILD    { ++$count }
    method DEMOLISH { --$count }
    method count    { $count }
}

my $red_car  = App->new_car( name => 'Red' );
my $blue_car = App->new_car( name => 'Blue' );

$red_car->speed_up( 25 );
$red_car->speed_up( 10 );

say $red_car->speed;
say App::Car->count;
[download]

toby döt ink

Comment on Re: oop, variable that counts the number of objects created Download Code

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Re^2: oop, variable that counts the number of objects created by perlfan (Vicar) on Jul 30, 2020 at 16:22 UTC
not germane to OP but generally relevant Nice to see this example. I should probably ask this in another thread, but what's the obsession with `has`? Can't we (everyone not just your modules) just have blocks all the way down or superficially support something that's familiar to JAVA programmers? At this point we're just cargo culting a failed declarative approach (IMO). What are we getting beyond classic Perl OO? (sincerely want to break this down for the benefit of the overall discussion): protected methods strong types/checking strong data encapsulation What else? If this has been hashed out before (a true breakdown), I'd be satisfied with a link. TY!	[reply] [d/l]
Re^3: oop, variable that counts the number of objects created by tobyink (Canon) on Jul 30, 2020 at 17:01 UTC
Why would declaring object member variables with blocks be familiar to Java programmers? `# Java class Car { public String name; public int price; public int speed; } # Zydeco class Car { has name ( type => Str ); has price ( type => Int ); has speed ( type => Int ); }` [download] Where would you add blocks to the Zydeco example to make it more like Java? toby döt ink	[reply] [d/l]
Re^4: oop, variable that counts the number of objects created by perlfan (Vicar) on Jul 30, 2020 at 18:45 UTC
Just a general thought, why is `has` so pervasive? Idk I probably should think more about what I am really trying to figure out. This is not about your modules specifically.	[reply] [d/l]
Re^5: oop, variable that counts the number of objects created by chromatic (Archbishop) on Jul 30, 2020 at 22:08 UTC
Re^6: oop, variable that counts the number of objects created by bliako (Monsignor) on Jul 31, 2020 at 09:38 UTC
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Re^6: oop, variable that counts the number of objects created by perlfan (Vicar) on Jul 30, 2020 at 22:43 UTC
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