Perl MooseX::Declare with method attributes MooseX::MethodAttributes

问题

I am trying to use Moose, MooseX::Declare, and MooseX::MethodAttributes to be able to use class and method keywords instead of package and sub and at the same time get the methods attributes, so I need this form of packages and methods:

class Moosey {
    method connect ($user, $pass) : Action GET  {...}
}

If I use sub keyword it will work with attributes but of course no method signatures, If I use method keyword, it will hang the script if I use method attributes.

Below is the code I am trying:

package Moosey;

use Moose;
use MooseX::Declare;
use MooseX::MethodAttributes;

class  Moosey {

    # this works fine
    sub moosey : Action { print "moosey called"; }

     # this line hangs the script
     # Error: Can't locate object method "attributes" via package "MooseX::Method::Signatures::Meta::Method"
    #method  moosey  : Action { print "moosey called"; }

    # this also does not work   
    #method  moosey  : Get ($name, $email) { print "moosey called"; }
}

1;
my $class = Moosey->new;
my $attrs = $class->meta->get_method('moosey')->attributes;
print "@$attrs";

My question is does these Moose modules allows me to do this.

回答1:

MooseX::Method::Signatures (which is what MooseX::Declare uses to handle methods) does support attributes, but they need to appear after the signature, not before it:

method foo :MyAttr ($arg1, $arg2) {  # NO
    ...;
}

method foo ($arg1, $arg2) :MyAttr {  # YES
    ...;
}

However, it does not seem to work with MooseX::MethodAttributes because they both try to override Moose's default metaclass for methods.

I would like to be able to say "use Moops instead". But that seems to fail for a different reason. A workaround is to declare the allowed attributes in UNIVERSAL...

use Moops;

package UNIVERSAL {
   use Sub::Talisman qw( Action Get );
}

class Moosey using Moose {
   method moosey1 :Action(FOO,BAR,BAZ) {
      say "moosey1 called";
   }
   method moosey2 (Str $name = "Bob", Str $email?) :Get {
      say "moosey2 called $name";
   }
}

Moops provides nice introspection for method signatures:

my @params = Moosey->meta->get_method("moosey2")->signature->positional_params;
say $_->name for @params;  # says '$name'
                           # says '$email'

But it doesn't provide much in the way for attributes. (Yet.)

TL;DR: no.

来源：https://stackoverflow.com/questions/24707056/perl-moosexdeclare-with-method-attributes-moosexmethodattributes

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perl

moose