It's a little sad watching people who live in the Perl echo chamber convince themselves that Perl use hasn't declined in the last years.
Overall Perl use may have declined, but good, effective, maintainable Perl use by people who're involved in the community is on the rise - and that's the group that I'm a part of, the people who write Perl as a robust, team-oriented, scalable production language rather than the PERL scripters of old (and my thoughts go out to the PHP and ruby communities who seem to have acquired a similar breed of idiot this time round the hype mill).
For all the talk of CPAN being so killer, there actually isn't much there that other languages don't also have. There may be more choice in implementation of a fairly common concept, but that's the Perl way. The "aha, I'll use Perl because this CPAN module implements exactly what I want, and nobody else does" moment rarely happens.
You can see a list of recent uploads here: http://www.cpan.org/RECENT.html
> There's tons of choice with date libraries,
Most everyone uses DateTime.
> or OO frameworks,
Nowadays choosing this one is simple: Moose
> or unit test frameworks
Test::More is pretty standard.
> For all the talk of CPAN being so killer, there actually isn't much there that other languages don't also have.
That is approximately the opposite of my experiences with the CPAN.
Perl is a great tool, in the tradition of the Unix command line. It is a testament to its success that is not considered to be a more powerful awk.
Indeed. Most of my day job programming is in C#, and I don't suspect that my employer would ever want a major product release written in Perl, but we have plenty of internal tools that are written in Perl, and new ones are always being created.
I believe he is the one who has most encouraged the tendencies which led to the Perl 6 debacle. His strong charisma has made it acceptable to have the following attitudes in the Perl 6 effort:
- Actual use by mortal programmers is boring; satisfying your desire to be brilliant and clever is what matters
- Complexity and obscurity are fun. Perl is good or popular because the language is complex, therefore the next version of Perl should be even more complex.
Perl 6 really has nothing to do with Perl 5. It's more like those movies that say "a movie by the producers of $THING_THAT_WAS_AWESOME" which neglect to mention the script and the director are different.
This is what Conway is claimed to be influencing:
>>- Actual use by mortal programmers is boring; satisfying your desire to be brilliant and clever is what matters [etc]
Go check who wrote "Perl Best Practices". Better yet, read the book.
(And please don't try arguing "REAL influence", or something...)
To avoid the [language war] trolls in stories about Perl, I mention Moose.
Since it is a better OO system than anything in the competition, they generally go away... :-)
Edit: I really wish Lisp was the competition today, I always loved it. :-( I've never used CLOS, but afaik Moose is directly inspired by it (MOP, right?).
You may find this Perlmonks discussion interesting, especially "stvn" comments: http://www.perlmonks.org/?node_id=655788
The MOP looks like a necessary tool for Perl's horribly designed OO that wouldn't be necessary for most other languages or could just as easily be implemented as a library. Python and Ruby both have what seems to be the equivalent of metaclasses. Most OO languages have some idea of what an attribute is. And so on. Once again, MOP looks neat, but it's certainly not unique to Moose.
edit: reading the MOP link more carefully, the idea of a class builder builder is more sophisticated than I originally thought MOP was, but as the link says, you're heading into esoteric territory at that point.
Safety and correctness.
My main point in all this is that, from my perspective, Moose may have a few bells and whistles beyond the base OO features of other dynamic languages, but these features are more 'nice to haves' than 'essentials. More importantly, these features could also be trivially added in other languages as libraries. Most importantly of all, none of these features is as important as starting out with a clean, well-designed language in the first place, and Perl is anything but clean or well-designed.
Duck typing suffers from the false cognate problem, and mixins suffer from false cognates and potential collisions. They also do nothing to ensure type safety or optional type-based compile-time optimizations.
More importantly, these features could also be trivially added in other languages as libraries.
Non-Moose Perl 5, Tcl, Lisp-pre-CLOS, Lua, and JavaScript to some extent demonstrate the "you can roll your own object system trivially!" fallacy, especially when you want to use libraries written by other people. Likewise, I'm not aware of anyone who's used roles in a serious project who wants to go back to object systems without them.
(On the other hand, you got a better answer than from me when Chromatic answered. :-) )