Re: Moose -> Mouse -> Mouse::Tiny/Muscle

Hey gang,

I uploaded Mouse 0.08 just now. It has no hard dependencies.
Scalar::Util is required only if you use weaken.
Class::Method::Modifiers is required only if you use
before/after/around. I'll see about inlining the latter. The only loss
in functionality is the feature set provided by Sub::Exporter. But, as
Yuval said, it is okay to make that kind of compromise.

I haven't gotten to a (one-file) Mouse::Tiny but that's next.

Shawn

On Tue, Sep 9, 2008 at 9:30 PM, Michael G Schwern <[email protected]> wrote:
> Sartak wrote:
>> On Tue, Sep 9, 2008 at 4:20 AM, Michael G Schwern <[email protected]> wrote:
>>> I looked at just copying in Mouse, but Mouse has dependencies which themselves
>>> have dependencies, some of them with XS.  Ideally, what I want is Mouse::Tiny,
>>> or as I like to put it, "Muscle". [2]  A stand-alone, single file, no non-core
>>> dependencies, 5.6 compatible implementation of 80% of Moose.  That way I can
>>> just copy it into the Test::Builder2 distribution and have a real OO system.
>>
>> I'd love to see Mouse itself go this way. There's little point in
>> having a lightweight Moose that has a number of dependencies
>> (especially XS). It looks like we could make all the dependencies
>> optional, and only required if you use the features.
>
> Excellent.
>
>
>> Here are Mouse's direct dependencies, and why we have them:
>>
>> * Sub::Exporter is used for a more powerful export. I use its extra
>> features (as a user of a Sub::Exporter module) very infrequently, so
>> being able to drop down to regular Exporter would be useful.
>
> It looks like extends(), has() and with() all depend on Sub::Exporter's
> ability to customize by caller.  However, that's easily emulated.
>
>
>> * Scalar::Util is used for blessed, weaken, looks_like_number, and
>> openhandle. It's in core as of 5.8, but if we need 5.6 then I think we
>> can make it work:
>>
>> - looks_like_number and openhandle are used only for the Num and
>> FileHandle type constraints. These aren't used very often as far as I
>> know, so perhaps we can delay-require Scalar::Util.
>>
>> - weaken is only used whenever you want weak refs for an attribute. I
>> personally do this with some frequency. But if you don't use it
>>
>> - blessed is used a lot. "use Mouse" also exports it. We could
>> probably provide an alternate implementation that uses ref and makes
>> sure it isn't a builtin type.
>
> looks_like_number(), openhandle() and blessed() all have short, pure Perl
> versions that can be easily copied.
>
> weaken requires XS and weak ref support, but it's perfectly fine to load that
> on demand.
>
>
>> * MRO::Compat is used for get_linear_isa. We could implement this in
>> Perl (and using mro::get_linear_isa if $] >= 5.10).
>
> It looks like that can all be separated from Class::C3.  I wonder what the
> performance hit will be?
>
>
>> * Class::Method::Modifiers are used for before/after/around. I wrote
>> this one, so we have more flexibility here. It's only a few pages of
>> code, so we could just add it into Mouse::OneFile, or again delay-load
>> it.
>
> That appears to only depend on MRO::Compat which we have to deal with anyway,
> so it looks like a straight copy is possible.  before, after and around will
> be useful for TB2.
>
>
> --
> E: "Would you want to maintain a 5000 line Perl program?"
> d: "Why would you write a 5000 line program?"
>