App::Easer and Moo


I tried App::Easer V2 and Moo together, they can get along apparenty.

In App::Easer V2 I’m relying upon bare OOP capabilities in Perl, i.e. basically bless and @ISA. Making use of the module in the right way takes care of setting up the hierarchy, inheriting from App::Easer::V2::Command:

package MyCommand;
use App::Easer::V2 '-command';

The -command does the trick:

sub import ($package, @args) {
   # ...
   while (@args) {
      my $request = shift @args;
      if ($request eq '-command') {
         $registered{$target} = 1;
         no strict 'refs';
         push @{$target . '::ISA'}, 'App::Easer::V2::Command';
      # ...

I was wondering how does this play with using common approaches to a more modern OOP in Perl, like Moo. I mean, App::Easer::V2::Command provides its own new method, so there is the potential for a clash.

From a small experiment I run (in example [moodu2][]), it turns out that they can get along if App::Easer V2 is used before Moo (like here):

package TuDu::Command;
use Path::Tiny 'path';
use POSIX 'strftime';
use App::Easer::V2 '-command';

use Moo;
use experimental 'signatures';
no warnings 'experimental::signatures';

   has time_format => (is => 'lazy');

sub _build_time_format ($self) { $self->config('time_format') }

# ...

Example run (with some data):

$ ./moodu2 list
o1 [ongoing] let's do it
o2 [ongoing] Go to the visit
o3 [ongoing] Help
o4 [ongoing] this is a new task
o5 [ongoing] This is a brand new task
o6 [ongoing] This is a task
w1 [waiting] Blurb the Birbs - but better

Inverting them does not make the program happy any more:

$ ./moodu2 list
cannot find sub-command 'list'

I don’t know the internals of Moo or how the method resolution algorithm works, I can only guess that method new comes from Moo and the whole thing stops working.

So… order matters.

Stay save everybody!

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