I am writing a constructor in which I want to initialize certain aspects of the object algebraically like so: 
 my $g = Games::Grid->new
    (border => 4, width => sub { $W/4}, height => sub { $H }, fill => 
+'=');

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What this means is that the width of the game grid is 1/4 the value of $W, which should be bound to the terminal width. The height is equal to the terminal width. And the grid should be filled with equal signs.

The following code in new: 

 {
   
    my $W = $self->{terminal}->{_co};
    my $H = $self->{terminal}->{_li};

    $self->{terminal}->{WIDTH}  = $config{width}->();
    $self->{terminal}->{HEIGHT} = $config{height}->();

  }

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is not working because the closure was evaluated as soon as I defined the hash and $W was not in its scope.

How can I delay the attempt to bind $W until I evaluate the closure within the constructor?

In reply to Algebraic Hash Configuration via Delayed Closure? by princepawn

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