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Comment by HankB99 | Hacker News Reader

I've used Perl off and on throughout my career, even working at one job that was pretty much exclusively Perl. I've also used Java and C/C++. I've done a lot of work with embedded systems where C was the order of the day.

But back to Perl. I always thought one of the best things about Perl was CPAN. I could nearly always find a module that would accomplish a specific task I needed and then I was just left to write the glue to implement that function (or functions) for my particular needs. I'm surprised CPAN is not mentioned. I wonder if it is still active. I also wonder about security of CPAN in todays environment. I find stuff like pypi and npm to be pretty scary.

I haven't started anything in Perl in quite some time. All the cool kids are using Python so I've been sharpening my skills with that. (But it's all hobby projects these days.)

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> But back to Perl. I always thought one of the best things about Perl was CPAN.

I'm a younger developer, so I wasn't around when Perl was super popular. I listened to the Corecursive episode about CPAN [0] and was really impressed. It's a good listen even if you're not that interested in Perl anymore.

[0]: https://corecursive.com/tdih-cpan/

CPAN was definitely the envy of other languages for many years but I feel most have caught up by now.

Kind of caught up. I don't think there's much like cpantesters and the strong emphasis on testing elsewhere.

Agreed, and the cpan shell too.

I haven't used the cpan shell for a long time `cpanminus` does everything I need with a great deal less pain.

> nearly always find a module that would accomplish a specific task I needed

Then you didn't have to write PC/SC smartcard code in Perl. Also most of the MQTT clients are crap, only Net::MQTT::Message is useful but then you have to write the network client yourself and if you also need TLS, good luck, the modules doing that have like 200+ failed tests. CPAN is great but if you need anything out of the ordinary you'll probably find modules in a state of disrepair, abandoned in 2010.

That's unfortunate but I suppose a consequence of a less active ecosystem. I don't recall dealing with that back in the day but it doesn't surprise me now, particularly with more recent technologies like MQTT.

I have written MQTT clients in Python and the module support was good. But then I discovered it was easier (for the most part) to use the Mosquitto cli utilities and pipe stuff to/from them. For cases where that was awkward, it was easy enough to write in C and use the PAHO libraries directly.

Yes, Python, Ruby and JavaScript have better MQTT libraries. I managed to write an async Perl client using POE (the networking code was already heavily using it, otherwise I wouldn't even pick POE since it's awful and also dead) and Net::MQTT::Message. Piping output into mosquitto_pub/sub was out of the question, since this was no hack but rather a service that streams data into the broker.

I suspect writing it in Ruby with async would also prove problematic, but there are the ruby-mqtt and async-io gems and one would use the MQTT::Packet for formatting messages and Async::IO for the networking code. Still a lot less painful than what I did with POE and Net::MQTT::Message.

MQTT.js is async already, you just import and use it in the browser, Node.js, probably Deno as well. Easy. It took literally five minutes to get the client enpoint working in the browser over WebSockets. One could even do it from the browser console.

> I'm surprised CPAN is not mentioned. I wonder if it is still active.

CPAN is indeed alive and kicking; https://metacpan.org/

The thing is back in the day 35,000 modules on CPAN was a big deal but if you look at https://modulecounts.com that's since been dwarfed by Python/PyPI (398,000), Ruby/Rubygems (173,000), PHP/Packagist (351,000) and JS/npm (2,116,000).

CPAN is still where the most interesting work is happening with Perl. Often blog posts like Dave's here will highlight features added to recent perl versions, which from outside the community looks pretty underwhelming. Probably it is, but that isn't as compelling as what you can get from outside the core.

While the core devs of perl concentrate on optimisation of the language and slowly add new features, the strong backwards compatibility approach constrains what can be done with it. The backwards compatibility is so important that development builds of the core will run against the entirety of CPAN's distributions' test suites to see if changes break anything there. This is know as "BBC" - blead breaks CPAN. If a change breaks something on CPAN then it needs to be reevaluated. I don't know if any other languages have an equivalent - running not just the internal test suite but also an enormous external one?

The nature of Perl means external modules can bend the language in some pretty interesting ways and build atop a strong foundation. The new features added to the language are slowly being used by more module authors to create features and libraries that are what you want to focus on.

See https://metacpan.org/pod/Task::Kensho for some of these.

I am not much into JS but I have seen countless jokes about JS/NPM having so many modules. I never understood why JS/NPM ecosystem has so many modules? I guess JS isn't that versatile language.

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