in reply to Re^2: Idea: Moose Mutal Coercion
in thread Idea: Moose Mutual Coercion

This is no criticism of the goals of your module.

But ... you knew it was coming right? ... Do you have a more realistic example of how and why it might be used?

The problem with using a toy example to illustrate the functionality, is that it ends up looking like a solution looking for a problem.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

The start of some sanity?

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Re^4: Idea: Moose Mutal Coercion
by educated_foo (Vicar) on Feb 15, 2012 at 13:58 UTC
    A less-distracting example might be a ball with mass, velocity, and momentum (calculate the third given two). I still think reaching for a lazy-building pile of Moose goop is wrong, since it's way easier to just have a cache: 
    sub momentum {
    my $self = shift;
    $self->{momentum} //= $self->{mass} * $self->{velocity};
}

    [download]
    but at least this may let people focus on the idea.
[reply]
[d/l]

      You think that the OP is suggesting that Moose herders use his module so that they can type this:

      package Equation_Problem; 
use Moose;
use MooseX::Invertible_Build;

has mass     => ( isa => Num);
has velocity => ( isa => Num);
has momentum => (
    isa => Num,
    invertible_build => {
        A => 'mass',
        B => 'velocity',
        via => 'A * B',
    },
);

      [download]

      To 'save' typing:

      package Equation_Problem; 
use Moose;

has mass     => ( isa => Num);
has velocity => ( isa => Num);

sub momentum {
    my $self = shift;
    $self->mass * $self->velocity;
}

      [download]

      Hm. It can't be that in(s)ane.

      With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
      "Science is about questioning the status quo. Questioning authority".
      In the absence of evidence, opinion is indistinguishable from prejudice.

      The start of some sanity?
[reply]
[d/l]
[select]
        No. I guess the OP wants a class which you can initialize with any two attributes, but you can then ask for all three.
[reply]

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