use Perl

• Thanks. (Score:1)

  by Stevan (6065)

  First off, thanks for the nice review, it is good to get feedback from new Moose users. The #moose echo chamber on IRC is obviously not so helpful in this regard.

  The default of ''is => "ro"' is badly chosen ...

  Actually the default is to not create any accessors at all. While it might seem useless, it is a perfectly valid use case, take this example for instance:

  has 'some_flag' => (
      predicate => 'is_some_flag_set'
  );

  This will create a predicate method for checking if the flag is
  • Re: (Score:1)

    by jplindstrom (594)

    It differs from Perl in that it wont accept an arbitrary value and treat it as true.

    That was what I was referring to. Maybe if it's advertised as these-are-the-Perl-types kind of type constraint it should actually conform to the Perl true/false idea, and if you want to stricten it up to only support 1/0/undef you use a different one (Bool vs Boolean) ?

    Anyway, it surprised me when using it, that's all.

    /J
    • Re:Thanks. (Score:1)

      by Stevan (6065) <reversethis-{moc ... {elttil.navets}> on 2008.07.08 13:27 (#63827) Journal

      I think perhaps you are mistaking a "value" for the "value of an expression". When Perl sees

      if (@foo) { ... }

      it evaluates @foo as an expression, and in that context it returns true. If I were to invent a "boolean" built in similar to the "scalar" built in, which forced "boolean context", then the above code would desugar into

      if (boolean(@foo)) { ... }

      Just as

      my $foo = @foo;

      desugars into

      my $foo = scalar @foo;

      Now in the context of Moose, when you assign a value to an accessor it does not impose the "boolean context" on it, so it only sees a value, and therefore does not pass the type constraint.

      - Stevan

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