[jasode]

>how Perl managed to become quite so profoundly disliked

I'm guessing the reasons are actually more conspicuous than computer science concepts of "undecidability" since most working programmers don't read academic papers to judge whether they like/disklike a programming language.

The conspicuous reasons seem to be a combination of:

1) PERL's usage of sigils.[1] One the one hand, it makes code compact and terse. On the other hand, many perceive the source code as "line noise" or "sigil hell". This is the opposite problem of other disliked languages like Objective-C where people complain it's too verbose.

2) PERL not having a constantly updated ecosystem that keeps up with new trends in computing. PERL was great for text munging (alternative to sed & awk). However, PERL wasn't extended as the driving language for dynamic web pages (Brendan Eich created Javascript instead of embedding Perl interpreter in Netscape browser), or GUI data entry forms programming (Java and C# gained popularity), or machine learning (Google developers designed Python to be 1st class in Tensorflow), etc.

tldr: PERL is perceived as "legacy" with ugly syntax

[1] https://en.wikipedia.org/wiki/Sigil_(computer_programming)

[Ultimatt]

Point 2 is kind of nonsense. The ecosystem is incredibly big and keeps up with most things. Name something then search here https://metacpan.org/ The main missing stuff is anyone marketing heavily their libraries and there being communities around them etc. Like probably no one knows what PDL is, even though it was around long before numpy+scipy etc. Before data science trended in the mind of hipster VCs and coders. The naming was to try and win over people from the IDL language, used mostly in image analysis in physics/geography. A niche crowd to be sure. Perl sort of never caught on to the modern style of advertising what its got. In the same way no one really advertises grep, awk or sed but lots of people still learn and use them.

[zbentley]

The size of the CPAN is certainly impressive. However, past a certain point, a big, multipurpose, monolithic Perl codebase being worked on by a ton of different developers is going to have significant problems caused specifically by the use of different CPAN libraries: many, many quite common libs do not "play well" with each other in quite simple cases. And I'm not talking about "I'm trying to glue together two third-party tools that weren't written with each other in mind", I'm talking "I have a request handler that once, an hour ago had to load and call a function in a given module, and is now issuing cryptic errors on all requests of a certain type because they happen to call a function in a different, totally unrelated module that worked before".

This is largely because of the sheer volume of weird global state inspections/mutations you can do in Perl--or I guess it's more accurate to say that Perl has a conveition of it being "OK" to heavily and frequently inspect and mutate global state. You can monkey patch in many languages, and sometimes it's even encouraged (Ruby), but only in Perl is it not uncommon to see monkeypatch removal or seriously altering replacement of core functionality. I've had modules hackily unload other already modules because the loaded modules' names matched a buggy load-time regex. I've had packages clobber text handling or encoding routines in other packages at compile time, or only after calling a certain function a certain way. I've had modules change the behavior of the core signal handling APIs so that any code that talked to them . . . didn't actually handle signals. And those are just the pithy examples that fit in a single sentence.

Now granted, this isn't a criticism of Perl-the-language but more of (depending on how you choose to interpret it) library authors who don't prioritize or even consider interoperability with other tools, or of Perl-the-community's conventions regarding when it's OK to go mess around in globally-stateful guts of code you don't control. You could also just as easily say that it's a symptom of the big, multipurpose monolith I had to maintain--which is valid, but other not-designed-for-huge-projects languages don't, in my experience, have problems quite this bad when they're forced to scale.

My goal isn't to cast blame, but to point out that CPAN is incredibly bloody far from a high-quality, stable, or usable code repository for certain very common use cases.

[Diederich]

> CPAN is incredibly bloody far from a high-quality, stable, or usable code repository for certain very common use cases.

Citation needed.

[zbentley]

Read the rest of my post. If you don't agree, that's fine.

[Diederich]

I read your post carefully, and I even agree with parts of it. There are major modules/module families that don't work together.

However, that's light-years from the claim that I quoted.

There are a lot of different ways of doing the same things in Perl the language and in the CPAN ecosystem. That's a strength and weakness. But in my experience, the authors of most of the modules care very deeply about doing things in a sustainable way.

[Ultimatt]

I agree there is a lot of dross on CPAN. I've also lived the frustration of seeing two kinds of exception handler TryCatch vs Try::Tiny in the same subdir of a codebase. The issue is really that a lot of basic modern functionality requires CPAN, and the core of Perl 5 is small and mostly not super helpful. Something akin to Moose in core as the new standard way to do OO would have been a good plan 10 years ago.

[jasode]

>ecosystem is incredibly big

I wasn't talking about the size of cpan because it's not relevant to my point. I was talking about Perl not being at the forefront of everyone's minds and being used as a 1st-class environment as computing entered new domains. E.g. instead of Sun or Microsoft taking an existing language like Perl and giving it a canonical IDE to let programmers write data entry GUI applications, they create Java & C# instead. When Google/Android decided on a development language for their smartphone SDK, they chose Java instead of Perl. It doesn't matter if cpan has mobile phone libraries now.

You seem to be taking my observations about Perl as some sort of veiled attack. I'm just reporting why and how Perl got to the state of being "disliked" today in programmer surveys. It's not about the "undecidability".

[Ultimatt]

Ok then your definition is corporate ecosystem then? Perl in general is hardly the stuff of scaled soft eng. in a mega corp. It wasn't designed for that, but to empower an individual to be highly productive quickly. With that in mind the ecosystem is super healthy, even by your definition. I'm more shocked Python has managed to bridge that gap, but so did Pascal at one point so I guess designed to be a teaching language wins out!

[jasode]

>It wasn't designed for that,

And I'm not "penalizing" Perl for that.

>I'm more shocked Python has managed to bridge that gap,

That's more to my point. Old languages like C++ and Python keep getting rejuvenated as 1st class drivers of innovation but Perl (the language -- not the cpan) keep getting ignored.

I was surprised when Google chose Python as one of the 1st class languages for its new Tensorflow instead of a new language like Julia. I do understand why they chose Python but nevertheless was surprised.

Same for C++. It gets rejuvenated in things like graphics programming (NVIDIA's CUDA SDK is C++ not Perl). And when Bitcoin showed up in 2009, it's canonical client was C++ not Perl. Also, updates to C++ via C++14 and C++17 were discussions that turned into reality whereas Perl 6's long development became a running joke about vaporware.

Perl5 and Perl6 don't really have any new stories like that where it gets rejuvenated. Therefore, it keeps dropping off everyone's radar as "legacy".

Whether Perl programmers are highly productive with Perl isn't really the issue.

[kbp]

> Same for C++. It gets rejuvenated in things like graphics programming (NVIDIA's CUDA SDK is C++ not Perl). And when Bitcoin showed up in 2009, it's canonical client was C++ not Perl.

Perl is not competing with C++; they're entirely different languages with entirely different usecases. Comparing it to Python is reasonable; comparing it to C++ is silly.

> Also, updates to C++ via C++14 and C++17 were discussions that turned into reality whereas Perl 6's long development became a running joke about vaporware.

Newer C++ versions are more akin to newer Perl 5 versions like 5.26 (May 2017), 5.24 (May 2016) etc. Perl 6 is a new language using some of the same ideas; comparing Perl 5 and Perl 6 is like comparing C++ and C#, not C++ and C++17.

[jasode]

>Perl is not competing with C++; they're entirely different languages with entirely different usecases.

Yes, I understand that C++ does not compete with Perl. My point is the rejuvenation stories, not the runtime or use case differences.

I use a utility every day called ExifTool[1] that's 100% Perl source code or very close to it. However, ExifTool does not keep Perl at the top of mind the way Tensorflow brings Python relevancy to a new generation of programmers.

[1] https://www.sno.phy.queensu.ca/~phil/exiftool/

[kbp]

> 1) PERL's usage of sigils.[1] One the one hand, it makes code compact and terse

Sigils have nothing to do with Perl's terseness; actually, they make code very slightly (one character per variable) more verbose. In Perl 5, $foo is a scalar, @foo is a list, %foo is a hash, etc. $foo[0] is the first element of the list @foo; it gets a $ because the element being accessed is a scalar. This is in contrast to most languages where variables are referred to like 'foo' and that's that.

[zbentley]

Utter and unabashed tangential pedantry: Perl should not be all-caps. The PERL "acronym" is actually a backronym (or "retronym" if you like): https://docstore.mik.ua/orelly/perl3/lperl/ch01_02.htm

[jasode]

The terseness isn't the variable name, it's the notation of the type:

  @foo 

... is more compact than C#...

  ArrayList foo = new ArrayList();  // C# v2
  var foo = new ArrayList();  // C# v3

And Perl

  %foo

... is more compact than C++:

  auto foo = std:map<string>;

[kbp]

But when you talk about Perl stagnating and losing out to other languages, the languages it lost out to were Python and Ruby, which don't require any type notation. It also lost out to PHP, which has sigils, but they don't carry as much information: $foo just means foo is a variable. Perl didn't lose out to C++ and C#; they were never really competing in the same domain.

In Perl, you write:

    my @list = (1, 2, 3);

Whereas in Perl's popular successors, Python and Ruby, you write:

    list = [1, 2, 3]

Saying the former lost out because the @ makes it unreadably terse is nonsense.

[jasode]

>Saying the former lost out because the @ makes it unreadably terse is nonsense.

Well, that's not what I claimed. I also wasn't really focused on "@%$" specifically but you had brought it up so went with it. (I get this weird feeling that I'm discussing with someone who's emotionally invested in Perl and he feels like I'm bashing Perl. Please let's us both stop this and make sure we're talking about Perl in a detached manner.)

Yes, strlen("my @list = (1, 2, 3)") is greater than strlen("list = [1, 2, 3]"). I wasn't talking about that. I was talking about things like strlen("@") < strlen("arraylist"). But... "C# doesn't compete with Perl!". Yes, that's true.

A realistic scenario where perceptions of "@" and "Arraylist" is compared would be a C# programmer working on an ASP.NET website or Javascript programmer working on Nodejs and then the company needs him to go fix an old website that was written in Perl ~15 years ago. The old Perl programmer left and C# programmer is stuck looking at Perl's "line noise". That irritated C# programmer then fills the Stackoverflow survey expressing his "dislike" of Perl. The C# and Javascript looked "readable" but Perl syntax such as "<>" looked like gibberish.

[kbp]

> I also wasn't really focused on "@%$" specifically but you had brought it up

My involvement in this conversation started with quoting you saying that one of the major reasons for Perl becoming disliked was "PERL's usage of sigils.[1] One the one hand, it makes code compact and terse". Perl's use of sigils has nothing to do with terseness, and since Perl lost its mindshare to Ruby and Python which to the tiny extent that sigils contribute to terseness/verbosity are more terse, I don't think that's a valid point about Perl's trajectory.

> I get this weird feeling that I'm discussing with someone who's emotionally invested in Perl and he feels like I'm bashing Perl.

I don't even know Perl, I'm just critiquing your logic.

> Perl syntax such as "<>"

'<' and '>' are not used as sigils in Perl.

[jasode]

>, I don't think that's a valid point about Perl's trajectory.

Again, the "Perl lost to Python/Ruby ... terseness" connection is your narrative, not mine. I feel you have my comments mixed up with someone else.

>'<' and '>' are not used as sigils in Perl.

I agree and I didn't say they were.

That's 3 cases of nitpicking something I actually didn't claim. I can only assume this over-interpretation of things I didn't write is a result of some underlying irritation that I caused. Let's just stop. Peace.

[psergeant]

Why do you write it in all capitals?

[jasode]

No good reason. Purely muscle memory that I picked up decades ago. Maybe I saw someone else do it[1] and just picked up a bad habit. I'll stop the all caps and write Perl from now on.

[1] http://www.perlmonks.org/index.pl?node_id=511722

[Ultimatt]

Because they don't know much about contemporary Perl. It's actually a really good indicator of if someone actually knows anything about the language post the 90s. I used it as a soft hiring filter on CVs. You knew almost as matter of fact any dev putting that on their CV was self taught from monster nests of legacy.

[ionforce]

I thought I was the only person who asked this.