Re^8: Perl Vs Ruby

[stvn]

See Moose - which looks pretty nice but isn't even trying to offer much above some OO syntactic sugar (nothing like a standardized collection / iterator interface, for example) on top of Class::MOP

This is because Moose is not trying to implement a standard library or collections framework, it is only trying to make OO nicer. And while I agree that a standard library is a good thing in theory, practice has shown that one size does not always fit all (see also - Ocaml's standard library, all the Java frameworks that have gotten traction in recent years, etc). Perl is a community (for better or worse) of strongly opinionated people, getting people to agree on some "standard" would take forever (see also - Perl 6 RPC process).

The problem with doing that, is that you'll end up with a fancy OO framework that isn't used by 90% of the code out there, which means you won't be able to use much of it when you're interfacing with most CPAN modules.

FWIW, Moose is built specifically to play nice with non-Moose CPAN modules and legacy non-Moose code (I have several partially Moosified apps in production). Moose would be absolutely useless IMO if it forced you to re-write everything in Moose and that was one of it's key design goals (otherwise $work would have probably just switched to Ruby or Python).

In languages like ruby & perl, OO is such a common need that the basic interface and conventions just HAVE to be worked out by the standard library,

I disagree with you here in regards to Perl. In Ruby they had to create a "standard library" of classes (Array, etc) because "Everything is an Object", whereas in Perl you could consider the standard library to be built-in (non-OO) arrays, hashes, scalars and the functions that operate on them.

[Joost]

I'll take your word for the compatibility features of Moose. I haven't seriously used it (yet).

I disagree with you here in regards to Perl. In Ruby they had to create a "standard library" of classes (Array, etc) because "Everything is an Object", whereas in Perl you could consider the standard library to be built-in (non-OO) arrays, hashes, scalars and the functions that operate on them.

The problem is, perl's standard containers are conceptually objects just like custom-made perl objects, except the interface to them is completely different. So different in fact, that you can't use the standard iteration constructs (like foreach and while each), or calling/accessing ops (like (), [] and {}) on anything that implements a "normal" OO interface. And THAT means you can't use the familiar iteration constructs on any user-defined object, unless it sacrifices easy access to other potentially useful methods.

In other words: the problem isn't that arrays and hashes aren't objects, the problem is that the perl programmer cannot reasonably define his own datastructures that can be accessed using the same interface the build-in types use. It's a problem of (access to/lack of) well-defined interfaces. And I stand by my assessment that tie() is an ugly hack that only half-way overcomes this issue.

[stvn]

In other words: the problem isn't that arrays and hashes aren't objects, the problem is that the perl programmer cannot reasonably define his own datastructures that can be accessed using the same interface the build-in types use. It's a problem of (access to/lack of) well-defined interfaces. And I stand by my assessment that tie() is an ugly hack that only half-way overcomes this issue.

That I will completely agree with, tie() is horrid and it would be nice to be able to define something that is compatible with standard @ and % without having to use tie() to get there. The inverse is possible now though via autobox and we have tried to make a semi-standard API (based heavily on the Perl 6 stuff) with Moose::Autobox.

[Joost]

Ooh, interesting stuff.

I hadn't heard of either. Cheers for posting that.