Just a couple of references, in case they are of use:

• Best GUI for Perl?
• GUI with Perl for desktop applications (perlmaven)

Thank you eyepopslikeamosquito...
I didn't realise there were so many Perl GUI's - next time I want to write anything for the desktop in Perl I shall try an alternative to Tk

• Perl and graphics: Is this about creating graphical user interfaces (GUI) - or about creating pictures and animations? For GUI, the choice is, well, difficult. For a somewhat narrower scope, SDL Perl comes with a book Writing Games in Perl (a bit stale, though). If it's about creating beautiful images, you could start with an app like harmonograph (based on Wx) and work from there (but see the third item below).
• to be used in more up to date contexts: That would make it difficult for Tk. While the widget demo provided with the library is very helpful, it shows a style which is very idiomatic to Perl - and to a somehow old-fashioned Perl style in particular. Also, Perl/Tk apps look a bit "old". On the plus side, to my knowledge it is the only toolkit which allows to define events on individual canvas items.
• An important aspect of is to get it running in the environment which your son wants to use, and unfortunately this isn't always trivial. So, I would be tempted to recommend WxPerl, but unfortunately it doesn't install cleanly from CPAN these days. For example, for Windows and Strawberry Perl there's the open Bug #129768; applying the patch suggested by Kai-Uwe Eckhardt in that bug report makes installation work and tests pass.

I'm not really recommending this for a 9 year old, but since we're on the topic of graphics in Perl, I'll go ahead and promote my OpenGL::Sandbox module, combined with the fact that it can run shader demos from www.ShaderToy.com. (but of course, so can javascript) Teaching a kid to think in terms of transformed coordinate spaces will go a LONG way in geometry and trigonometry later in high school and college. I'm doubting a 9 year old can grasp that yet, but who knows, everyone has different strengths. And sometimes early exposure can lead to later understanding.

Edit: Also, there is CmdlineGL if you want to teach him how to do 3D graphics in bash.

I'd add Kotlin to your post: to be able to program for mobiles seems to be our destiny.. or doom :)

L*

There are no rules, there are no thumbs..
Reinvent the wheel, then learn The Wheel; may be one day you reinvent one of THE WHEELS.

Well, he's 9 year old, when do you expect him to enter the job market and how can you know which technology will be on-date then? :)

I would let him play and experiment, I think Perl is a very good starting point for the concepts of most dynamic languages out there (mostly because they borrowed heavily from Perl or Perl did from them)

He could chose his path then, if he really continues to be interested in programming at all.

After all, the top-quality of a programmer is to be able to adapt to a new language.

It's true you can find a lot of teaching material out there for Python, but my experience is that quantity is not quality.

This "Python is easy" mantra is encouraging a lot of "easy" minds to write half-baked summaries.

> My 9-year old got completely hooked into Perl

Firts I should say: lucky you and him :)

> Now it would be desirable if he could go into graphics and user interfaces

In this situation for GUI I would opt for Prima: I never used it it but I have look at it several times with a growing interest. It is modern and under active developping but a mature project.

Tk is old and has many quirks but still works well: can I prodly point you to my Tartaglia-s-triangle, picwoodpecker, Stone-Jam and Discipulus-15-puzzle?

Stone-Jam is a simple game and maybe my code ( the core is under 200 lines ) is not that bad to understand.

For graphics I used GD in the above picwoodpeaker and in tk-jepg-custom-rotator

GD is not that easy to learn ad use but he can start under your guidance.

My best wishes to your son (..and you)!

L*

PS I have also a fun project where graphic is rendered in terminal: the demo of the project is usable but the overall design is flawed and I have no more will to correct it: Game-Term

git clone  https://github.com/LorenzoTa/Game-Term
cd Game-Term
perl -I ./lib ./demo/00-start.pl
[download]

"My 9-year old…"

OT: Programming For Kids might be helpful for further inspiration. Assumed that I understood your question right.

One area that is transferrable is SVG. Perl has some decent modules for this such as SVG, and it can be fun to compare carefully written SVG to the output of inkscape doing the same thing, which I have found hideous.

Regards,

John Davies

Though it saddens me to see most teenagers fiddling with their mobile phone as they walk down the street, your son might just be motivated by the prospect of developing mobile phone apps in the future ... so you could try introducing him to one or more of the following programming languages:

• C++
• Java (programming language)
• C Sharp (programming language)
• Swift (programming language)
• Kotlin (programming language)

Apart from being used to develop mobile phone apps, all the above languages have excellent graphics libraries, and superior performance to scripting languages (update: because they are all statically typed). See also:

• Android software development (wikipedia)
• iOS SDK (wikipedia)
• Comparison of programming languages (wikipedia)

Oh, and just in case it helps teaching Perl to your son, I also keep a list of Learning Perl Links.

all the above languages have ... superior performance to scripting languages.

If you have one (and I'm sure that if anyone has it will be you :-) I would be interested to see a reference for this as it pertains to Java. My experience has been quite the opposite.

---

🦛

hippo you've caught me unprepared! ... so I can feel a future meditation brewing on this complex and interesting topic. :)

Static typing usually results in compiled code that executes faster. When the compiler knows the exact data types that are in use (which is necessary for static verification, either through declaration or inference) it can produce optimized machine code. Some dynamically-typed languages such as Common Lisp allow optional type declarations for optimization for this reason.

-- from Type system (wikipedia)

As indicated by the quote above, my performance assumption of the five listed (statically typed) languages (including Java) was based solely on the well-known general properties of static vs dynamic typing.

When I programmed in Java years ago, I remember the HotSpot technology muddying the performance waters when attempting to compare Java to C++ because (at least in theory) Java HotSpot could perform gradual dynamic performance optimizations at run-time (based on HotSpot profiling and the specific hardware it was running on) which C++ could not (update: nowadays it can, thanks to Chris Lattner's LLVM and Clang). Despite that, I've always loved C++ and disliked Java, and would always back C++ against Java in any specific benchmark shootout. :)

Extra References Added Later

• Just-in-time compilation (wikipedia) - e.g. via Java HotSpot and C++ LLVM
• Adaptive optimization (wikipedia)
• Java performance (wikipedia)
• HotSpot (virtual machine) (wikipedia)
• Comparison of programming languages by type system (wikipedia)
• The Computer Language Benchmarks Game (wikipedia)
• The Computer Language 22.05 Benchmarks Game
• The Computer Language 22.05 Benchmarks Game Summary Charts
• Re^2: What's Perl good at or better than Python (Game of Life, LLiL, Rosetta and Performance References)

I'll stick by my recommendation of javascript, because the last thing a kid would want to do is have to write their program twice so that their iPhone friends and android friends can both see it. And don't forget the hassle of tooling and publishing on the app store.

I recently came across an IRC client called The Lounge which is the single best written JavaScript GUI I've ever used. I haven't had time to pick apart the source code yet, but they built that thing with the best that web technologies have to offer. You can browse to it from any common web browser, and on mobile devices there is a button in the UI to save a link to it onto the phone's desktop as if it were a native app. It's indistinguishable from a native app and functions better than half the apps on my phone. And best of all, it's free and allows me to cross off my TODO list item for that web-based multi-platform IRC bouncer I always intended to write, and without regrets, because this is way better than what I would have created.

And don't forget the hassle of tooling and publishing on the app store

Ha ha, not to mention the cost. Every hobbyist Apple developer I met at work actually lost money! Admittedly, they were Apple die-hard fans and novice iPhone developers with a full-time day job ... but the annual Apple Developer Program fee turned out to be greater than what they earned from their App! :)

should I really let him go deeper into outdated technology

Perl does not fall under the "outdated technology" banner in my opinion. Sure, it might not be the latest sexy, shiny language but that does not make it outdated.

Having written code in a number of languages with varying degrees of success, I feel Perl is the easiest and most versatile among them. Hence it is very much my language of choice.

There is a rather intetesting article that addresses this issue of Perl being outdated. It points out just how different Perl is now to when Perl 5 first appeared despite the name implying they are similar.

I wish I had discovered Perl in my early days of programming. I learnt BASIC from a textbook and wrote lots of code by hand with a pen and paper before I ever got the opportunity to test that code on an actual computer! I was about 12 at the time...

LanX's post just now -- mentioning domm's bicycle routes from Vienna to Frankfurt -- brought back happy memories of domm here at Perl Monks. He was quite a character at the monastery back in the early 2000s. Feeling nostalgic, I checked out some of his old nodes and noticed his two highest rated posts:

• How to introduce 8 year olds to (Perl) programming?
• Space Invaders

might assist you in your quest of introducing programming to your nine year old son!

Is obfu of interest to a nine year old? I have no idea, so I'd be interested to learn of your son's reaction to domm's Space Invaders ... and which obfus appeal to him from The Top Ten Perl Obfus. :)

Interestingly, one of his sons has become a game developer :-)
map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

Another "more-or-less graphical" user interface that is quite useful is ncurses, which gives you quite good interfaces in the terminal. Curses::UI is a good start for this.

You can make nice user interfaces, and as a bonus, this also works over SSH. Which is quite a useful feature when you are working remotely on a system that had no monitor, keyboard and mouse. Like, for example, a Raspberry Pi stuffed into some other project like an autonomous RC car.

Interesting Topic! ;)

maybe it's a little bit off topic, but I feel sad to see many guys recommend Java ,C++ etc(in perlmonks!).

In short, computer language is another language for human. So the most importance are can-evolve, the ability of expression (especially new thing), easy use for communication(Making Easy Things Easy and Hard Things Possible) and free style for expression(TIMTOWTDI, ). I think perl perfectly meet these requirements. that's my 2c.

Love is all I bring inna me khaki suit and ting
>>> Nah pop no style, a strictly roots <<<
Nah pop no style, a strictly roots
(youtube warning, severe addiction warning)

meaning: https://www.theanswerbank.co.uk/Music/Question38159.html

TINA to TIMTOWTDI

bw, bliako

Dear All,

thank you a lot - these were superb answers and I have now a lot of homework to do.

It seems that half of you are suggesting jumping to a different language. I have considered that often (the most serious contenders would be Rust, JavaScript, and Kotlin), but I do concur with xiaoyafeng and others - Perl is not at all bad for him, versatile and playful, and also just beautiful, I find. And he can learn the concepts here as well as anywhere else.

His case is however a bit untypical - I am not looking for beginners' stuff. He made his way through "Learning Perl" and "Intermediate Perl" very swiftly, and now I can hardly separate him from "Programming Perl". But he usually writes very self-referential stuff that doesn't do much - he plays with the concepts, builds modules, objects, regexes, complicated data structures with references, that sort of thing. But that is also partly because he does not know to do anything but text-output on the console. So I am in the weird situation trying to interest him in maybe writing a game or so. As for the rest of the tech stack: It's all Linux only, and he has little acquaintance with or interest in phones, and he does have some sense of HTML and CSS.

I do feel glad he took so well to a language that I like and that we could explore it together (he is already way better than me), but I also do feel bad seeing him a bit stuck or confined (although he does not experience it as such). Anyway, I think with all the new options you gave me, for now we will stick with Perl and see what these various suggestions can do.

One note about "outdated technology": Yes, I get it's not quite yet so. I guess I am more worried about the trajectory. Perl and Python (which really never did it for me) are pretty much the same age. However, Python has been going places (partly for the very reasons I dislike it) while Perl, even though it keeps hanging in there, has very few new users and uses. Even more importantly it seems unclear whether the community can productively unify behind a consistent development of the language. This is why I fear it may be on its way out. I really hope I am wrong.

My vote is for Perl/Tk (mainly because I still use it a lot). It uses the basic widget callback paradigm which applies to many other systems, and for that reason it's reasonable to learn.

And since one of my philosophies is "always show code", here's a very simple drawing program in Perl/Tk:

#!/usr/bin/perl

use strict;
use warnings;
use Tk;

my @lines;

my $mw = MainWindow->new;
my $c = $mw->Canvas(-width => 900, -height => 900,)->pack(-side => 'bo
+ttom');
$mw->Button(-text => $_->[0], -command => $_->[1])->pack(-side => 'rig
+ht') for
  [ Exit         => sub { $mw->destroy } ],
  [ 'Clear Last' => sub { pop @lines; draw() } ],
  [ 'Clear All'  => sub { @lines = (); draw() } ];

$c->Tk::bind('<1>' => sub
  {
  push @lines, [ &xy ];
  $c->Tk::bind('<Motion>' => sub { push @{ $lines[-1] }, &xy; draw() }
+ );
  } );
$c->Tk::bind('<ButtonRelease-1>' => sub { $c->Tk::bind('<Motion>' => '
+') } );

MainLoop;

sub xy { $_[0]->XEvent->x, $_[0]->XEvent->y }

sub draw
  {
  $c->delete('pen');
  @$_ >= 4 and $c->createLine(@$_, -smooth => 1, -width => 5, -tag => 
+'pen') 
    for @lines;
  }
[download]

Maybe others can post a comparable program in other GUIs for comparison purposes.

Mojolicious::Lite and Imager are a powerful combination for writing graphical applications with Perl.

Also, check out PureBasic. It's a paid software, yes, and it's expensive (about $70-80 to purchase), but it makes GUI programming very easy (not as simple as HTML & JavaScript, but still on the easy side), and it can compile to Windows, Linux and MacOS. It comes with an extensive Help file and lots of example programs to learn. And it's easy to learn. Okay, it's totally different from Perl, but it's not hard to learn at all. By the way, there is a Freeware version too. It's called XBasic. It also runs on Windows and Linux and makes graphics programming fun and easy!

Now that I know a bit more about the use-case after your second post I can give my 2 drachmas. 1.5 of which has already been given by fellow monks here.

I usually don't bother with GUI (in the usual context). I put all my effort in building the logic as a non-GUI Perl application and then combine it with Mojolicious to react to user requests locally or remotely and totally compatible with all the OS which support browsers which support standard HTML and javascript. I add extra functionality to the "endpoints", e.g. "login", to communicate (read input params and send out a response) with the user in 2 different ways: HTML and JSON. If the user uses the browser then HTML rendered on their browser can do as much as a modern GUI can do. JSON is intended for allowing an "app" to interact with your back-end. For this last scenario and if you don't want to bother too much with "apps", Android (and I guess IOS) provide a Webview widget which renders HTML and executes JS. Which makes this prospect a click more powerful than a browser because Webview can inject HTML+JS and execute code in the "app" space. So, Javascript, as mentioned already by NERDVANA and Mojolicious by anonymonk. The drawback here is that there can be need for advance JS skills like XHR and the reactive-programming challenges therein. Otherwise JS is cute and easy.

Secondly, I love to scrape! Scraping should be given the "hero of the internets" award. There's data everywhere and scraping it, legally, combining, storing etc. can give you a playground to do super-powerful things. Perl is in par with any other language here with its reliable LWP::UserAgent and CPAN modules to parse received data. Plus Perl's seamless use of regexes (whereas Java needs some boilerplate to do basic regex, yikes).

Thirdly, in some cases I need very fast network response and number crunching. Then I resort to trusty C and C++. There are C-native, open source (a very important criterion in whatever you decide to use) libraries which offer access for, say, curl and OpenCV from C and C++. Perl is perfect for calling C executables. No fancy XS is required, just a simple system() suffices. You want some face recognition? Easy peasy with above setting and OpenCV.

Fourthly, there are languages dedicated for doing certain things. One of which is R. A totally head-hitting-the-wall language with steep learning curves but with an amazing gamut of open-source packages for doing virtually anything in the statistics, bionformatics, data-processing fields. All with easy multi-threading or GPU support. Again, you do not need to write a huge R script and, ouch!, a GUI. All you need is to follow the basic Unix mantra: do one thing and do it well and create a small script which you can call from Perl. You want some sentiment analysis? Easy peasy with above setting and R. There's also LaTeX, a language dedicated to typesetting of the highest standard. You want to render some PDF? Easy peasy with LaTeX (which has a Perl driver so you don't need to shell-out).

Finally, you can't go wrong when you are backed by an OS like Linux*, which is my Fifth and last point. So, for me, nah pop has no style, I strictly roots and I am enjoying every single keystroke of it.

bw, bliako

*) Don't make the mistake to think Linux and OSX are the same thing. Big mistake, keep away from OSX as it has become worse than M$ in the well-known aspects plus a few more perversions that the apple people invented all by themselves. (a good post must contain a rant).