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I've been coding php for years, and now i have to finally make my own project, and i want it very optimized and shiny. So, i've been searching around the net about which programming language should i use for my needs (fast, secure, easy-understandable, customizable) and all points to -> Python. So I decided to go on, but i just can't feel "home" when writing python (inc Django app...). I got used to PHP's syntax, and my IDE (PHP Expert Editor 4.3) makes php look awesome, so now i just can't go with python.
Maybe there is something which has php's syntax (let's say per example: Perl)...but the advantages of a high-level programming language (aka Python)?
Use what you like and what you know. If you want to try something new that's ok .. but if you want to start a serios project now I would not use a new language for this.
Maybe better look what you could do better with php. (Maybe use a better template engine or design clever classes or whatever). Many huge webapps are developed with php and are working very well.
Also I would not say that Django is a highly optimized framework .. if you want to look into something new well documented you could check the flask microframework http://flask.pocoo.org/
This line of work requires you to adjust to different syntaxes (even in PHP alone you need to know sql and js and Css and html too...).
So the answer is no, there is nothing like what you ask, and you better get used to that :-)
b.t.w is Python really faster than PHP?
If you've been coding in PHP for years, then maybe PHP is still the right choice for you? As long as your project is related to web (by the way Facebook uses PHP!) you should stick to it.
Python is really easy and fun to learn, but as any other programming language - it requires time to get into it. And for web projects, you'll have to catch up with frameworks and maybe servers (e.g. tornado).
If you'd like to do something on enterprise level, Java is also a good choice. But never as easy and as fun as Python :)
I'm a PHP developer. I like PHP! It is a really good language if you know how to use it, but I know it allows very bad design sometimes.
It reminds me of JavaScript which has good parts and bad parts. One particular project, CoffeeScript, tries to focus only on the good parts, forcing you to write good code.
I was thinking if something similar could be done with PHP... A new syntax that would be compiled only to good PHP code taking advatage of all the new and exciting stuff we can get with PHP 5.3.
So, getting ahead of some people, I'll ask: Why create a new language on top of PHP if you can just use Ruby or Python or something else?
PHP is easy to deploy anywhere
The language itself has a lot of good features and ideas
There are lots of good libraries written in PHP
...
So, my real questions here are...
Is this a stupid idea? Why would it be? Do you think CoffeeScript is stupid?
How do someone starts to create a new language on top of another? I know nothing about this, but I would like to learn. Where to start?
The idea is definitely not stupid, especially if executed well.
I like coffeescript a lot, but it has it's approach has downsides as well. Debugging a coffeescript script still requires you read the generated Javascript code, which can be tedious, since you haven't written it actually yourself.
I've understood that Jeremy Ashkenas, the creator of coffeescript has started to work on coffeescript after reading "Create your own freaking awesome programming language" by Marc-André Cournoyer.
Good luck!
The reason CoffeScript is a good idea is that if developers want to run code in a client browser they have to use javascript; so the only way to program in a different language is to allow that language to be convertible to javascript.
I'm not sure the same really applies to server side programming. If you've got issues with PHP and want to use a new language there is no real advantage to having that language generate PHP.
On the other hand, a language that was very similar to PHP, but fixed some of the flaws would be a great idea.
Heh, great idea. My thoughts, some contradictory...
There are precedents for civilizing bad languages by putting syntax preprocessors in front of them.
In the early days of Unix, Fortran was popular and about the only portable language because most machines had no C compiler. But the vanilla Fortran of the day didn't even have block structured if-then-else, just a goofy single-statement if or an if-goto. So, the Ratfor language was implemented as a preprocessor for Fortran-66.
I believe there were (are?) Cobol preprocessors that presumably dealt with the verbosity and limitations of early Cobol dialects.
To this day Unix-derived systems ship with a macro processor called m4.
Several CSS preprocessors are available today, most notably Sass and LESS.
But...
Just let it die, and the sooner the better
The problem isn't really in the syntax.
I don't see much of a JavaScript-PHP parallel. JavaScript is a great language. It's kind of the opposite of PHP.
I'm not sure why you say that PHP is a great language. It's one of the worst. Every decent feature is a patch or repatch in a recent version.
As you noted, there is a fixed-up version of PHP already: it's called Ruby and, as a language, it's near-perfect. There is another fixed-up version called Python. The world would be better off in the long run if we support the better systems.
It is here now. A new language which is to PHP what CoffeeScript is to Javascript. (I.e., awesome.)
SNOWSCRIPT
Snowscript code looks like this:
fn how_big_is_it(number)
if number < 100
<- "small"
else
<- "big"
PHP output looks like this:
function how_big_is_it($number) {
if ($number < 100) {
return "small";
} else {
return "big";
}
}
All it needs now, is you.
If it would be to PHP what something like sass is to CSS, I'd be interested. But what would exactly would you want to add? Or would you just want to weed out the bad?
And what would you consider to be the bad?
Writing a PHP syntax transformer would probably be a neat project.
However, don't forget that PHP's standard library is a huge mess. Cleaning that up, would be a far bigger task.
The more I am thinking about this, the more irrealistic it sounds. The reason is simple: There actually are such language proprocessors already. Two of them (though not using PHP as implementation, only as compilation target) can be found here. But simply nobody uses them.
Yes, if the compiler itself were written in PHP, probably more people would use it. But I really can't see a way how to get this popular enough to be worth the work.
Another big problem is, that people mostly are used to their awesome code-highlighting, code-completing, code-inspecting IDE. Without getting IDE support probably merely anybody will use it (and IDE support can only be obtained by having many people use it...)
Thoughts?
I can see writing compilers to JavaScript (because the web imposes it upon us), but this sounds like a waste of time.
Haxe already does this, although it's not specifically targeted at PHP (linked to the Wikipedia article instead of their website because I'm afraid I'm going to get exploited if I visit the real site...)
PHP is easy to deploy anywhere
...as are its vulnerabilities.
I know it allows very bad design sometimes.
That's a bit of an understatement, it doesn't even have a module system, has no encapsulation, and has tons of silly things such as dynamic name resolution.
PHP is slow enough as it is, do you really want something an order of a magnitude slower?
Java is much more easy to deploy anyways, and lets you drop down to the bytecode level if you want. Java also gives you access to moderately sane libraries.
This is something I have thought about already often. PHP just is messy at some points.
Actually, I already have a project PrePHP focusing on providing PHP 5.3 functionality to PHP 5.2. But it adds some minor language features, like func()[0]. I haven't developed this project for some time and it definitely isn't "clean", but it shows, that what you want is possible and actually even not that complicated.
If you are serious about this, I am perfectly willing to collaborate with you.
Very interesting idea and if it come to life i think that i wan't to be involved in :)
For start You may check and read this position http://www.amazon.com/Masterminds-Programming-Conversations-Creators-Languages/dp/0596515170 (iam reading it now). It makes clear how really complicated is to maintain own language.
I agree that PHP definitely could do with some improvement, right now it allows for too much fooling around.
Some things I'd like to see
Static Typing
Required indentation
Proper use of objects (using arrays as objects is just stupid)
Then again, maybe I should just drop PHP and start working with Ruby or Python.
I'm like 8 years too late, but I'll answer anyways for anyone else who stumbles upon this.
Hack is a language developed by Facebook to deal with some of the issues of PHP, since Facebook had a large PHP codebase. Hack adds some nice features on top of PHP such as gradual typing (what TypeScript has) and generics, among other features, and gets rid of some of the more dangerous PHP features. Hack was at one point a superset of PHP, but is no longer completely compatible after removing some of the worse PHP features.
This is slightly different from what you were asking, since at this point Hack has its own interpreter, written by Facebook, but this started out as "better language that compiles to PHP", so I thought it was worth mentioning here.
It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center.
Closed 10 years ago.
I have a heavy web dev background with PHP. My reasons for learning a functional programming languages are:
to improve my programming skills. It was heavily suggested that learning a FPL helps. this has high priority because I want to be better and better.
learn a general purpose programming language to solve tasks like scripting (OS scripting, text manipulation etc..)
to be used as an alternative for PHP in web development.
Also which has the better community support, tutorials and books and the better web application framework?
Feel free to suggest other languages.
For functional languages, learn both Scala and Clojure. You'll learn new ways of thinking from both of them. Go learn some Reia and Erlang while your at it too.
Seriously, the more languages you have under your belt, the better off you'll be as a programmer regardless of the language you end up using.
Rant: "What language should I learn?" questions are getting tiresome. The answers should be the same every time, yet no one gives the correct sage advice. Instead, everyone spreads FUD and suggests that the language they happen to use for their day job is the one you should learn. Poppycock.
I've tried both Scala and Clojure recently, based on similar motivations. Here's what I found:
Scala is enormously versatile and powerful; Scala lets you define types with great precision and it allows you to define DSLs that are terse and clean. Scala has a lot of cool constructs that one wishes Java had, including a bunch of functional extensions. But when it came right down to it, I ended up coding imperative Java in the Scala language because the complexity of all that cool stuff overwhelmed me.
I did some Lisp back in University, and always had a hankering to get back to it again. Some really cool cutting-edge stuff is done by very smart people in Lisp, and in very few lines. I wanted to be one of those smart people, or at least try to be like them. But I never really understood Scheme, and I missed my "infinite supply of libraries" from Java. I couldn't see myself writing a GUI in Scheme, and had trouble envisioning a Web application.
Then I tried Clojure and it seemed like everything clicked into place. Clojure was intentionally made more outsider-friendly: There is an attempt to cut down on the parentheses and to use different parenthetical punctuation for different situations. Treating things like arrays, text and XML as sequences, combined with a powerful set of sequence functions, made a lot of problems quite simple, as does the support for arrays and hashmaps. It's (intentionally) like functional Java. The functional mindeset takes a bit of getting used to, but nowhere did I find it as approachable or as enjoyable as in Clojure. My code hardly needs loops any more, yet it's more clear about where it's looping/sequencing, and more concise. I can do mutable state if I really need to, but I have to be explicit about it; in exchange, that state is protected by Clojure's concurrency mechanisms. Concurrency, then, becomes almost a no-brainer, sometimes my code executes safely in parallel with no conscious effort of my own.
Not coming from Java, this will not seem very useful to you, but Clojure can do anything that Java can, including fully compatible .class files. Most importantly, it can interface with all Java libraries, and that ability alone will make PHP seem like a toy language to you.
My suggestion is to learn JavaScript.
I mean, really learn it.
Here's what a self-professed Clojure advocate has to say about Scala. Make up your own mind, of course, but you may find his perspective useful.
Scala Vs Clojure — Let’s get down to business
Scala vs Clojure — Round 2: Concurrency!
You may also be interested in what he has to say about PHP vs Clojure.
That's a very difficult call. Personally, I think Scala is more useful as a general language for web developers. There are many web frameworks for it, or adapted to it. On the very quick&dirty side, for instance, there's Play. On the full-fledged with excellent Comet support side, there's Lift.
But you talked about learning to program in a functional style. In that regard, there is no way Scala can compete with Clojure. Scala can be used in a functional style, but it makes sure you don't have to. With Clojure, on the other hand, doing anything but functional style is painful.
So, if you want an alternative to PHP, I'd bet on Scala. If you want to really learn functional programming, Clojure.
Finally, let me state that I do not think Clojure isn't a general purpose language, or that it can't be used for web development. I just think Scala is more on both regards.
Get a bag of cement, harden up and Learn You a Haskell, for Great Good!
It's purely functional, so you cannot fall off the ship.
It's general-purpose with loads of libraries (including a web application stack), and no VM startup time penalty (JVM languages are not great for OS scripting and the like, since you have to start the JVM every time).
Jumping form PHP to Scala or Clojure is going to be a huge culture shock. PHP is very focused on quick/dirty getting things done (or 90% clean with the last 10% dirty (-:), whereas functional programming languages force a certain correctness and abstractness onto your thinking. Before you get to Scala or Clojure, you're going to want something inbetween. If it was me, I'd
Pick my final target as Clojure, since (as I understand it) you get the entire Java standard library with Clojure, making it immediately more useful than something pure like Scala
I'd spend some time building something in Java, just to get a feel for a strongly typed OO language. I picked Java over C# (or even ZendFramework style PHP) because it will prove useful once you arrive at Clojure. Google Web Tools might be a good place to start with this. It's kind of web development, but very very Java like and not at all PHP/HTML like.
Spend some time looking at the guts of jQuery, and either develop your own jQuery module or add a core feature. This will get you used to the functional way of thinking, while applying it to a problem you're familiar with.
Final bit of advice: Try to embrace the common methods of the language/platform you've chosen. Don't try to bring your style of PHP coding to either language. Although it will seem easier at first and let you get some kind of results, you'll miss the point of the exercise, which is to think differently and more broadly about problems.
Good luck!
If you are looking for a good alternative for PHP, I suggest Python and Ruby. If you need a Functional language with good support for web development - learn Erlang. Here are some projects/frameworks that will help you create highly scalable web applications in Erlang:
Yaws - An Erlang webserver particularly well suited for dynamic-content webapplications. (Also see this Apache vs Yaws benchmark)
Erlyweb - A component-oriented web development framework written in Erlang and designed to work with Yaws.
Erlang Web - The Erlang Web is an open source framework for applications based on HTTP protocols, giving the developer better control of content management.
Nitrogen - An event-driven web framework for Erlang.
It is also one of the few languages that is specifically designed for building fault-tolerant, distributed software.
While it gets less press coverage than Clojure and Scala, I'd really recommend you to take a look at Fantom: http://fantom.org/
It's like the best of all both worlds and really should deserve more attention.
I'm a new convert to Clojure. It's making me expand my mind but it's approachable enough to be fun and productive. I'm a happy customer.
But
PHP and Clojure live in different universes. I've had some introductory dabbling in FP languages, and a few false starts into other Lisps before embracing Clojure. For a less experienced developer coming straight from PHP, Clojure might be too much of a culture shock.
As a reasonable compromise between the two, and a language that is scripty enough to let you approach FP on a gradient rather than a plunge, I recommend Ruby. Ruby is modern, clean and elegant. In its JRuby incarnation, it's even fast. Learning Ruby and playing with Rails is enjoyable and instructive.
Though Scala is my favorite language for now, i think it's not the best choice to learn FP. It's mainly OOPL with good support of FP. I would suggest to start from Haskell to quickly dive into FP. You will learn how the following concepts of FP work (which are not just supported, but enforced and ubiquitous in Haskell):
1) powerful static type system with type inference
2) lazy evaluation
3) side-effect free computing
After dynamically-typed "pragmatic" PHP and pure functional "academic" Haskell you will have quite full picture of programming languages landscape.
My $.02 is to check out Perl. I may sound like a geezer, but keep in mind that Perl has CPAN (http://cpan.org) and many very, very helpful online resources.
Ruby is probably the most "functional" mainstream language that's also good for scripting. Python is a close second, but ruby's habit of implicitly returning the result of the last expression in a function/block is the tiebreaker for me.
Both have excellent web frameworks (Rails and Django, respectively), and both will definitely broaden your horizons after programming PHP. At the same time they will allow a lot of opportunity for incremental learning.
Neither of them use S-expressions and both allow imperative programming, so there won't be anything to force you to give up the imperative style cold turkey.
Finally the much-lamented TCL is basically Scheme as a scripting and extension language. I'm not sure where it's at these days, but the ArsDigita Community System was written in TCL.
Web development depends ENTIRELY on: First, the quality of the web-framework and second the tools for development. I do not know why you want to move to functional languages for programming web applications.
Python allows some functional constructs for programming and it has frameworks and tools. Lua allows the same level of functional programming and it does not have either high quality frameworks for web development or tools, however its simplicity/primal-nature is its elegance.
Now as a puritan I'd say look at haskell, but that is counter-productive :D,. You my friend are looking for Python. I have not evaluated Ruby, but it might have some functional constructs.
May not appear so fancy, but I strongly suggest JavaScript.
A lot of years ago I was strong at PHP development, but then switched over to Java, C#, C, Objective-C. During my Java time I stepped deeply into JavaScript and did some pretty cool things with it. Someone I know developed an entire client-side temporary lightweight DBMS. Just have a look at Ext.js what they do with JavaScript. It's so underestimated, but doesn't deserve it. I suggest you google for "Douglas Crockford Video". At Yahoo he has created several excellent presentations about JavaScript, also I suggest you get the book "Javascript - The Good Parts" from Douglas Crockford, and "JavaScript - The Definitive Guide". Both the best JavaScript books available. And you'll be amazed what's possible and what a beautiful language it actually is. In fact, you can do AI with it, it has Lambda, there's actually nothing really "cooler" than that! What a pitty it's only used for clientside scripting. Few people know JavaScript can be used for serverside programming as well, but that's really rare / not well documented.
And thanks to Adobe Air you can bring JavaScript to the Desktop.
It would be an optimal addition to your PHP knowledge. It's always good to do related stuff. You can be the best Web Developer, or the best Desktop Software Architekt. But our brains are too slow to grasp all proffession needed nowadays to be the Guru in multiple directions. Beeing the Guru is essential for success, I think. Some friends of mine just do one thing: Beeing the Guru. They study their entire life one small subject and are extremely successful. They earn 5 times as much as any I-can-do-it-all-but-know-just-5%-in-this-topic-Developer in a quarter of the time only.
So I also suggest: Write a 600 pages PHP book before you forget your PHP knowledge while doing something totally different.
I did forget almost everything I knew about PHP and JavaScript, but in those early days I definitely was one of the expert guys who showed others a lot of stuff. Now it's a pain I have to ask so many basics again to recall them in my tiny brain. By writing your book, you'll recall your PHP expertise very fast even after a few years of doing something different, because it's your book, fitting your brain, from your brain. And you'll not loose your PHP-expert status even after several years of doing something else.
Good luck.
I tried Scala and found it a bit much (huge amount of operators that you have to recall how to use). But that could just be me. I've heard that Clojure is more functionally pure and closer to Lisp, but haven't checked it out.
F# is Microsoft's take on functional languages, you may want to check it out. I hear it has been used for several projects in industry.
I would suggest learning languages that have frameworks beyond the web front end such as Java EE (Java EE[JSP/JSF] + Java) or .NET (ASP.NET + C#, etc.). That would give you a bit more leeway with your career options, and you would be able to connect server components to a web front end with (relative) ease.
i was wondering if anybody knows of a nice scripting language that can be embedded into php?
Javascript would be favorite and although there are several attempts they are either much too shaky/slow/outdated (phpjs, j4p5) or a real pain to get up and running on shared hosts (pecl spidermonkey).
The background is: I would like to have a language that is used to control php on the server but it should also support some logic, so yaml, xml or json just isn't enough. I've looked into LUA interpreters and mediakwiki's "Winter" but they all either rely on external engines or have powerful binding whatsoever.
pecl spidermonkey binding's appears to be the most complete where you can register vars, functions and whole objects to the js-engine. Does anyone know of any system or language that might come close to what I am looking for?
best
rolf
I've not seens many engines that allow another scripting language to be enabled in PHP :-(
Even on PECL, there doesn't seem to be lots of entries (see the "languages" category, for instance : only one, which you already know)
And on PEAR, I don't even find anything that would match your criteria...
I've played with Spidermonkey a bit (see this article on my blog, in french), and it's kinda fun, yes. But it was not really stable a couple of months ago when I wrote that article -- and there have only been a few commits since. So, I understand why hosting companies would not provide it on their servers...
Even if I'd like them to : could be great to allow non-PHP developpers to develop scripts for your application !
A question though : why do you want/need another language than PHP ?
What I mean is PHP is already installed on your server, you obvisously have experience with it, and it's a quite powerful language... So why do you want/need to work with something else ?
Using PHP's eval, you can even think about executing "dynamic" PHP code (Yep, eval is eval and all that, I know ^^ )
Another option, using stuff like "exec" and the like would be, if you are on a Linux server, to launch some kind of shell-script ; but I would definitly prefer coding in PHP than shell, and I'm certainly not the only one ^^
Anyway, keeping an eye on the answers you might get, which could interest me quite a bit too ;-)
I understand your concern. Even for trusted sources, PHP provides more access than is necessary to the whole environment of the web request. Even if the scripters are trusted and even if they can only harm themselves with a scripting error, a more constrained scripting environment would be easier for them to use and easier for you to support.
You want something that can be sandboxed off, that can only access resources you explicitly assign to its scope, and that executes in a "play within a play" runtime environment rather than in PHP's own.
One approach is to use a web templating language for user-submitted scripts. These provide a certain amount of control (variable assignment for example), and close off other options, for example you can't write an infinite loop. I've used Velocity for this purpose in Java applications; I think something like Smarty might work in PHP, but I don't have direct experience of using it for that purpose.
Another approach, if what the scripts are required to do is constrained by the domain, is to implement a Domain Specific Language (DSL). I mentioned that in this answer.
Apart from that, I don't know of any pure-PHP implementations of scripting languages. It's something I'd be interested in myself.
Symfony has the ExpressionLanguage component:
The ExpressionLanguage component provides an engine that can compile
and evaluate expressions. An expression is a one-liner that returns a
value (mostly, but not limited to, Booleans).
...
The purpose of the component is to allow users to use expressions inside configuration for more complex logic. For some examples, the Symfony Framework uses expressions in security, for validation rules and in route matching.
An example of the language is below:
# Get the special price if
user.getGroup() in ['good_customers', 'collaborator']
# Promote article to the homepage when
article.commentCount > 100 and article.category not in ["misc"]
# Send an alert when
product.stock < 15
I'm reading The Pragmatic Programmer and I'm on the section where the authors suggest that we learn a new language every year. I'm currently a PHP developer and I'm wondering, what should I learn next?
I'm looking for a language that will help me improve my skills and help me with my daily tasks. Something useful.
Any suggestions?
[Edit]
Awesome answers guys! Thanks.
I'm still contemplating your answers and I'm leaning on studying Python or a functional prgoramming language as you guys have suggested (maybe Lisp).
Going for the option of learning something new, rather than something a bit like what you have done before.
C++ or C
A low level language that requires manual memory management and teaches you how things work at a lower level. Good community base and is one of the languages that a programmer should learn.
I would suggest one of these over assembly as although assembly is even lower level it is pain to produce a project. Learning a language like C or C++ will have the bonus of allowing you to learn assembly very fast if you ever want to do it, as there are relatively few new concepts compared to going from Java to assembly.
Haskell
A purely functional language that totally changes the way you look at some problems. It takes a lot of effort lean if you are already used to a imperative style of writing code.
It has the great advantage of teaching you the joys of recursion, and even if you are never payed to write a line of Haskell it should impact the code you write in other languages, allowing you to see better and cleaner solutions.
Java or C#
If you don't use PHP in an Object Oriented way (Not just using classes, but features like inheritance as well), then these languages force you to write in a OO style. I wouldn't recommend these if you are happy with OO programming.
Python and Ruby seem to be a relatively painless transition to/from PHP.
I'd go for Java or C#, so you learn something that is not another scripting language.
JavaScript.
And I mean really learn it, not just "enough to get by" the way the trend seems to be. I've seen otherwise-great (on the server side) web developers that can waste 2 days on a trivial JavaScript problem because they don't understand it at all.
I don't think there is a language that a developer will come across more often than JavaScript, and when you need to use it, you need to use it: you won't have the freedom of picking some other language to run on the clients browser. The good news is that it shouldn't take very long to grasp when compared to some other programming languages.
A good place to start is with JavaScript:The World's Most Misunderstood Programming Language
I believe it would be strongly beneficial for you to try and pick up on one of the popular functional programming languages as they require a completely different mindset and methodology for solving problems. They really allow for you to program elegant yet minimalistic solutions to difficult problems. Some of the more common languages include:
Erlang
Haskell
Lisp
Whilst I agree learning a new language is a good idea - make sure you are learning them and not just collecting them. For example - I come from a Java background and I keep catching myself writing in other languages in the way I'd write something in Java and not taking advantage of the new language's facilities. I'm sure you wont - but just be aware that it's a natural thing to do so keep an eye out for if you start doing the same!
As for which I'd learn; I'd second learning Ruby (plus optionally Rails if you want to do web apps) - it's a very nice language and quite an easy transition from PHP. The "Pickaxe" book from pragmatic programmers is a good place to start.
If you have access to a Mac - I very much recommend learning Objective-C and Cocoa. I certainly learnt a lot by studying these - I think more than any others I felt that understanding these made me a better all round developer. As for books - start with Kochan's "Programming in Objective-C" for the language side, then progress on to Hillegas' "Cocoa Programming for Mac OSX" for the GUI side.
Good luck!
I started off learning PHP after C. Then I discovered Perl and I never looked at PHP again. The reasons? Perl, like PHP, was dynamically typed, but far more modular. The Camel book about Perl was a delight to read. Running a Perl script from the command line was far quicker than PHP which needed all possible libraries loaded - Perl permitted me to choose what extra functionality I wanted at run-time keeping simple scripts light-weight. The Perl community is relatively advanced compared to other languages. The Perl language lets you program in a variety of styles, from procedural, to OO.
Functional languages seem to be gaining interest I'm planning on looking at F# primarily because I'm working with the Microsoft stack most at the moment.
I'd also recommend looking at topics that aren't language specific such as improving OO skills, using design patterns, and anything else that helps refine your skills as a developer to make you more of a craftsman rather than collecting languages that you won't get to use on substantial project and therefore will never really master.
Python + Django if you want to stay in scripting.
C if you want to understand how it works behind the scene.
C (as in C, not C++) would be my suggestion. It will instantly make you appreciate just what interpreted or higher level languages actually do for you (or save you from, depending).
It is also the first logical stepping stone to C++, though I know a lot of people who just dived into C++. Learning C first will (as above) either make you appreciate, or hate C++ even more.
To be a really well rounded programmer, you need to deal with managing types on your own, as well as managing memory without the safety net of a garbage collector. It used to be that those two were prerequisites for being a programmer at all.
Besides, think of all the fun you could have writing your own PHP extensions :)
This could turn into a debate.
My suggestion is to learn a new language that has something to do with your existing skills.
My "first language" was C, which brought me to C++ and Visual C. When I took on consultant jobs I enter the realm of PHP.
Starting from here, I am collecting skills in Javascript and jQuery, since they are tightly coupled with PHP. (DOM, CSS, and HTML aren't languages, so they don't count here.)
Or maybe you want to take another direction and go for SQL.
Choices is yours and crossroads are everywhere.
Not sure if you are programming PHP under the MVC model? But if you are not that is another good methodology to learn.
Examples: Zend or CakePHP
It totally depends on what you want to do. I don't think anyone can say what you should learn next, but rather share you with our experiences that will help you make your mind. After all, the decision for your next language should be based what what kind of applications you want to develop (desktop, mobile, web, etc).
I'll share you with my experience. I used to be a PHP programmer and I faced the same question, what do I want to concentrate on. I ended up to learn Java and I've been happy with my choice. Here are some of the reasons why I think it was a good choice
Java is a widely used language in the corporate world. This means that with good Java skills you'll be likely to find (more easily) a (better) job, more so than with Python or Ruby skills (disclaimer: this can of course vary between regions and countries, this was the case in my area)
I had done lots of web sites and applications with PHP and I've loved the web as an environment. Still, I felt that PHP wasn't quite the language to create full blown enterprise applications - that was something I also wanted to do - to be part of making large enterprise applications. Luckily, with tools like GWT or Vaadin I've been able to create enterprise applications which run in the web environment - all in Java. That was like a win-win for me, I was able to create large software for the web.
Java has forced me to think more Object Oriented, something I've benefited when writing PHP as well.
Java is multi-platform, so it is easy to write applications for linux/mac/windows or even for mobile devices (Java ME)
My two cents.
It depends on your motivation for learning the language.
If you want to learn a new language to do your day-to-day work more effectively I would suggest Python or Ruby. They are popular languages that are both highly productive to work in, and can be applied to a wide range of programming tasks. As someone else has pointed out there are versions for both the JVM (Jython and JRuby) and for .Net (IronPython & IronRuby) so if you want to learn either of those platforms they are a good way to start. They are also both easy to learn and fun to use. My preference is for Python, but that is probably because I have been using it for many years.
If you want to increase your employment options then go with the most popular languages used in business - this means either Java or C#.
If you want to expand your mind then I suggest a version of Lisp. I recommend Clojure - it is a dialect of Lisp that runs on the JVM and gives access to all the Java libraries. There is an excellent introductory book in the Pragmatic Programmers' bookshelf.
JavaScript (preferably through jQuery and Ext.js)
RegExp (preg_match flavour)
SQL (MySQL, PostgreSQL, SQLite dialects)
XSLT (and XML)
Each is very different. Each serves different purpose and each is very useful for PHP web developer.
If you want to try something different I'd go with
ActionScript (great opportunities)
C# (great IDE)
Python (complex ideas, misleadingly simple syntax)
Rebol (fun of having strange constructs work flawlessly on first guess)
Lisp.
(Or some other functional language.)
I coded in PHP for years and then took a (functional) Lisp class. It was four weeks of wtf %#f pain and then pure joy. Understanding functional programming, and especially recursion, really gives you and edge when coding PHP (or any other solution-oriented business language).