I am trying to learn Prima and trying to make a window menu by writing the code from the Prima's official book example: 
#!/usr/bin/env perl

use Prima qw(Application Buttons MsgBox);

my $window = Prima::MainWindow->new(
    text=>'Hello world!',
    menuItems=>[
        '~File', [
            ['~Open', 'Ctrl+O', '^O', sub{message('open!')}],
            ['~Save as...', sub{message('save as!')}]
        ]
    ],
    size=>[200, 200]
);

$window->insert(Button=>
    text=>'Click me',
    growMode=>gm::Center,
    onClick=>sub{message("Hello!")}
);

run Prima;

[download]
But the menu doesn't appear on the window and in console, there is an error message:

menu build error: submenu is not an array at /usr/local/lib/x86_64-linux-gnu/perl/5.30.0/Prima/Classes.pm line 180.

I've broke my head, trying to figure it out. I don't see any problem with the Array structure, building the menu.

In reply to Prima Menu by igoryonya

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