Thread: Web developing languages

Lol you guys.

I really like this community a whole lot more now.

To be fair, usenet is a place no one should want to be. I remember a 10 page discussion on the proper way to write a for loop, and it's not like the content was all worth reading. After about page 5, maybe earlier, they'd lost my attention.

It was something like how these things are different.

Code:

for(std::vector<int>::size_type i = vec.size(); i >= 0U; i--) ... 
for(std::vector<int>::size_type i = 0U; i < vec.size(); i++) ...

IIRC they knew that one of those would process the vector backwards but that was almost unimportant compared to the other points raised - such as repeated calls to member size(). Though, I do remember that one person pointed out correctly that the second version is more correct than the first if the container changes size in the loop.

Yeah. It was that sort of discussion.

I didn't participate... I think.

Originally Posted by Elysia

I'm not sure the first one is correct since size_type should be unsigned, which means the loop goes down to 0, loops, reduces i to unsigned max, which is greater than 0 and continues forever.

Mmm, well I could be misremembering what was actually wrote - though I admit it would have been better to use something signed. I don't remember.

As for the second one... calls to .size() actually matter! I did a quick test on MSVC, and it added an overhead of about 20% on optimized builds even with aggressive inlining, so they were right about that. Cache the size if it is not expected to change.
As for backwards or forwards... it doesn't seem to matter. The processor prefetcher is good enough to figure it out, I guess.

That you can be so succinct is why the length of the discussion surprised me.

@ItzBlue, my suggestions:

• Make sure you can create HTML pages (I recommend HTML5 and CSS3 in particular) by hand
  
  Your scripts will have to generate HTML content, and being able to do it by hand makes it easier. CSS is practically required for any complicated layouts. Use validators to make sure your pages conform to the standards, then check with different browsers (there are web services that help with that) to see if they render your pages correctly.
   
• Learn Javascript
  
  Even if you intend to do only server-side scripting, it is very useful to know what and how stuff can be done in Javascript in the client browser.
  
  Also, due to obnoxious advertisements, many users block Javascript by default, so being able to fall back to reasonable behaviour (say, losing any nice visual transitions, but none of the functionality) is sometimes enough to convince users to un-block ads on your sites. "Don't be a dick" can be a commercial advantage, even if the marketing people are too dysfunctional to understand it.
   
• Learn the details of the HTTP protocol
  
  Mostly, server-side scripts only need to worry about HTTP protocol details such as cache control and page aging, but having a good overall picture of what is transmitted and how the system works, definitely helps in tracking down bugs and causes of other problems.
   
• Get a basic understanding of TLS/SSL encryption and web security
  
  This involves understanding what a certificate is, what a certificate key is, what a certificate chain is, what is a certificate authority, and so on. At minimum, you should know about the typical scenarios -- man in the middle, eavesdropping, spoofing, and so on.
   
• Read up on character sets, filtering, and escaping
  
  Especially USians seem to think that there are only 26 letters. Which is only true for ASCII. However, we've got this fancy Unicode nowadays, and a very nice character set called UTF-8, we can use to support all kinds of writing systems. It's a bit weird when you get to know it, but it's surprisingly easy to work with.
  
  When data is saved or retrieved, there are usually certain characters or character combinations with special meaning. I'm sure you've heard of SQL injections? Bobby Tables? They work, because the programmer assumed the user would not use an SQL separator character in the inputs. Avoiding such issues is simple -- you can either filter them out, detect and reject input containing such, or use escape sequences or quoting to defuse them (make them non-special). Learn how to do those.
   
• Learn about POSIX access control model
  
  Those who learn web programming on the Windows platform, often get really frustrated when porting their web application to a POSIX platform (Linux or FreeBSD or OpenBSD etc.). The typical solution is some variant of chmod 0777 * , which is akin to going to a dark alley, pulling down your pants, drinking a bottle of hard alcohol, and expecting nothing bad to happen.
  
  (It does not help that even the Apache SuEXEC security model is braindamaged -- by default allows script drops -- but it seems like very few web programmers have even a rudimentary grasp of the POSIX file access model, and on how to leverage it to make their applications secure. It's not hard, but learning to do it right is. )
   
• Have fun on multiple architectures
  
  One of the best features on the web is diversity. We know that monocultures are bad -- just look at bananas; if we're unlucky, we might not have them in our stores in a few years (the resistant variants do not transport well). Use the diversity as a source of fun, and as a source of learning.
  
  One good way to do that is to use virtual machines. You don't need a top of the line machine, especially if you use a non-graphical OS on the virtual machine. You might wish to add RAM to your machine, though; I typically give 500MB to 1GB to each of my virtual machines to run with, and that's plenty enough for a Linux-Apache-PHP/Python stack with a database (MariaDB, Postgres, etc). If you already run Linux, try FreeBSD or OpenBSD instead in a virtual machine. Put your server on the virtual machine, and you can use your main OS browser as if it was on a remote machine. (As far as I know, all operating systems have good virtual machine "players" you can use for this, for free.)
  
  Try out different languages; you might find one that fits your needs best. Play with the online tutorials -- I think all web scripting languages have pretty good tutorials online, if you just look for them. Learning the basics of multiple languages (actually, different types of languages) in my experience helps widen your viewpoint, producing better programs as a result (although not everyone agrees with me).
  
  Don't get locked up on an idea or a language; keep your eyes and mind open. Being curious and open-minded will let you see more of the whole, before you decide on a comfortable niche to get better in.

I don't know all that much about html5 to be honest but I like the new container tags like <video> and such, and the free codecs to go with them. The web needed embedding multimedia made simpler for a long time.