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Anyone who has programmed for any length of time has an opinion about comments in code. They're essential. They're not essential. Commenting is actually worse than not commenting. It runs the gamut. I'm beginning to understand more and more that comments are actually a disctraction to clean, clear, concise code. Especially when writing in Python, it is possible to write code that requires no comments, but is still 100% understandable and discoverable. Sometimes a line or two is required to explain something not clear from context, but it's rare.

After reading a piece by Steven Smith entitled Comments in Code Indicate Functions Trying To Escape, my lead programmer Troy Melhase (i.e. my "boss"), who is a strong proponent of clear code/no comments, wrote:

Yes. Instead of writing comments, write code that doesn't need
comments.

Clear, and concise, just like his code. After musing on it a while, his ironic streak kicked in, and he composed the following "epic tome," as he describes it, that so clearly illustrates the many useless blocks of comments I have seen in my time as a programmer. He gave me permission to post it, so here you go! Enjoy.

(BTW, visit Troy's blog. He's written a Java to Python translator, and has a really cool stock-trading and analysis application.)



Now, this doesn't preclude documentation--we use doc strings at the beginning of files, functions, and classes quite heavily--but in-line comments in code are rare.

"There are a lot of nice things about PHP, it's just that the language isn't one of them."

from Paul Bissex

'Nuff said

I came across this writeup a couple months ago, and composed a reply (via an e-mail to a colleague), but never posted it.

Some people think objects have failed.

My response:

Objects have "failed" in that they've tried to be the be-all, end-all solution to all problems, while not being powerful enough to be the be-all, end-all. On the other hand, they've succeeded in that they are a good (often great) tool in many cases. I often find that objects are nice just for state-encapsulation: keeps me from worrying about certain details at that moment; I might not even be abstracting anything of note.

And I think it comes down to this: procedural, functional, and OO programming tools are just that. You use one or the other where they might be the most appropriate and most practical. Take these few lines from a script in a project I'm working on: (disclaimer: yes, I wrote them).



That is an interesting combination of functional (only two state variables: 'f' from a surrounding loop, and full_name) and object oriented (file and string.Template methods) programming. And the combination works, works well, and is only one logical line of code, to boot.

I don't think it's a matter of object, functional, or procedural styles failing, it's about having a good knowledge of all three, and their capabilities, and being able to make realistic and practical decisions about what will be the best in a given situation. It's also about using a language that lets you combine the three in a mix that works best for you and the given requirements.

(In this case, that language is Python, but that's peripheral.)

The interview is long over, the offer letter has been signed, and my two-week's notice has been given, so now the story can be told. As many of you know, for the the past year and a half I've been working at EE Internet. The time has come to move on.

A few weeks back, I came across a job posting on the AK LUG mailing list from a company in Anchorage looking for developers (programmers). I replied and asked if it would work as a telecommute job from Fairbanks. The answer was: "It's a slim chance, but let's give it a try." So, after sending them my resume, I flew down to Anchorage for an interview on September 25th. They liked me enough to make the telecommuting thing work, and I start work on November 5th.

I'll be working for S&K Aerospace a Montana native corporation, and the only non-Alaskan native corporation doing business in Alaska. They are a military contractor developing technology solutions for the armed forces in Alaska. I will be doing web application development, mostly in Python (woohoo!).

The best part is, I'll be working from home, so will get to be around my family so much more. We're all looking forward to it, and are very thankful for this opportunity. Crystal and I have been praying for a work-from-home job for me probably as long as we've been married, and God provided this job.

I'm excited!

In my job at EE Internet, we do a lot of remote data collection, including collection from cameras. Now, the makers of these cameras have figured out how to put the date and time as a graphic in the image itself (Umiat Airfield) but for some reason they haven't figured out how to embed that same information in the EXIF Data for that image. Very aggravating.

So, Python to the rescue. I came up with a script that extracts the area given, converts it to black and white, inverts it (because these cameras have light text on dark background, and OCR doesn't seem to like that), and then feeds that file to a command-line OCR program. It then takes that text, parses it for the date, and then prints it out in any date/time format desired. Works quite well.

Here it is in all its glory.

Comments, improvements, critiques, etc., are always welcome. And yes, you can post comments pointing to another program/project/whatever that does what I did and does it way better.

• It requires Python's PIL image library


• It defaults to using the gocr command. This is available in the 'gocr' package in Ubuntu. It also seems to work well with ocrad, which is also available in Ubuntu.


• There should not be any symlink vulnerabilities in this as the exclusive lock is kept on the file while there is data being written to it. Once the data is written, and the file is closed, then it is passed to the OCR program as an input file. Then, it is removed.
  

UPDATE: Modularized it so you can call it from the command line, or import it into your own Python script and call it that way.

The Firefox web browser has an extention called IETab which enables you to open a tab and browse websites via Firefox, but using the Internet Explorer rendering engine. This can help, for instance, if a site staunchly proclaims itself "IE only" and will not make changes for alternate browsers. Over at Hacking for Christ, Gervase Markham has a post entitled "IETab Considered Harmful?". He references the Slashdot article about MovieLink suggesting that users use IETab so MovieLink doesn't have to go to the "trouble" of making their web site Firefox compatible. Gerv observes:

The harm is that this 'solution' still excludes everyone on a Mac or on Linux, and its availability also makes the site far less likely to change to support Firefox properly. In other words, whereas before Mac and Linux users could add Windows Firefox users to their numbers when petitioning sites to upgrade to support web standards, the existence of IETab divides those two groups and gives those of us using non-Windows operating systems, and those who want to see sites supporting standards properly, far less clout.

Very true. The problem I have with IETab, however, is one of security. If you are using the IE rendering engine, you are opening yourself up to all the problems, standards non-compliance, and security holes you'd have if you used Internet Explorer directly. I keep telling friends, family, clients, and colleagues to use Firefox for better security. If there are sites out there encouraging users to "just install IETab to use our site," most of that security advantage will be negated.

At the conservative end, I think IETab should carry a big, fat warning along the lines of "This plugin is for development and testing only! Using it may compromise your system's security!" On the extreme end, I would have it done away with altogether. If you need multiple versions of IE for testing, on the Linux side of things, there is IEs4Linux, which allows you to install and run multiple versions of Internet Explorer on your Linux machine. I'm sure there is something similar for Windows. For Mac, you're still stuck, as IE no longer is available for Mac (at least last I checked). I suppose you could install Linux under Parallels and then install IEs4Linux.

So, yes Gerv, IETab is harmful, but not only for the reasons you bring up.

One of the touted benefits of Open Source software is the ability to "go in and fix it yourself" when your software isn't working the way you want. And while that is a great benefit, sometimes you don't have time to fully understand all the code and fix it on your own. That's when the other benefit of Open Source comes into play: direct contact with the developers.

Recently, I was setting up an instance of the Serendipity blog publishing software at work. Since we are in the process of migrating to MySQL5 from MySQL4, and since they are both running on the same database server, the way you reach the MySQL5 server is non-standard (it's running on a non-default port of 3307). There were two modules to access MySQL in Serendipity: the "old" mysql PHP module and the "new" mysqli PHP module (completely unrelated to the "old" and "new" database servers). I tried to specify the database host name as databaseserver:3307 (which is the usual way to do it), but using the mysqli module, it failed. With mysqli the host, db, user, pass, and port are all separate fields in the function call to connect, so you can't pass it databaseserver:3307. I posted about this error on the Serendipity user forums, and in two days (mostly because the author is about 10 hours ahead of me), we had debugged the problem, and he had written a few lines of code to change the mysqli connect call to handle the case of someone giving host:port as their host name. Pretty easy, but can you imagine getting a two-day turnaround from a commercial software vendor?

Shortly after this happened, there was a blog post by Giuseppe Maxia, a systems analyst and database designer, about a bug being opened in the MySQL bugs database and, with the help of two contributors from the MySQL community, that bug being closed just 11 hours later. Now that's the power of open source community.

Don't you wish Microsoft fixed bugs that fast?

In previous posts, I've alluded to the fact that I was learning Python for a project that was getting under way at work. I never did say what the project was, however, so here we go.

The company I work for, Engineering and Environmental Internet Solutions (EEI) is a sister company to Global Watersheds Scientific (GWS). GWS (via EEI) does much remote data collection around Alaska using data loggers connected via the Internet (including satellite), radio, and even cell phone. This data is collected and displayed (both textual and graphical representations) on a variety of web pages, and is distributed to a variety of clients. See this page for an example.

Quality assurance (QA) and quality control (QC) on this data, however, if done, must be done by manual inspection. Needless to say, this is a labor intensive process. The goal of this project, dubbed Photizo, is to create framework that will provide data processing, QA/QC, and data visualization, all in an automated fashion.

What does "Photizo" mean? The project name derives from a Greek word meaning "to enlighten, render evident, to give understanding to." The purpose of Photizo is to analyze data and give insight and understanding into said data, "rendering evident" the function (or malfunction) of a data collection network. Thus, the name Photizo (pronounced foe-tee'-zoh).

We are currently in the design phase, and things are going well. Python will be a good fit for this project, and give us great flexibility in our implementation, especially in areass where we must be able to accommodate various inputs (such as a variety of data file formats) or creating a framework to test data that will allow us to add and modify tests without editing the core code.

You can learn more, and keep track of progress on our wiki: photizo.eeinternet.com. If you have questions, comments, or suggestions on this project, feel free to drop me a line at joshua (at) eeinternet (dot) com.

Jon has a post about getting started with Django. Welcome to Python, Jon. I'm sure you'll enjoy it. As I've posted about before, I've greatly enjoyed my foray into the world of Python. While sticking with "pure Django," especially if there is a CMS system on top of it, may mean you don't see Python much, if you start creating filters and editing templates, you'll probably dive right in to the language.

If you have programming experience, snag a copy of Python in a Nutshell. If you don't, grab Python in a Nutshell and Learning Python. Both have served me well.

And of course, if you have a question, ping me. I'd be glad to share what I've learned in my short, but productive eight months of learning Python.

Python is a fun language, and easy to learn. I'm sure you'll have a great time.

My fellow blogger and former CDE colleague put up a few random thoughts mostly inspired by, it seems, by his trip to O’Reilly Emerging Technology Conference. I'll respond to a couple.

The trend seems to be: managers and accountants and investors have PCs, the hackers have Macs, the Ubergeeks have Linux.

Well, I guess that makes me an Ubergeek. Or not. But I do enjoy using Linux. However, with trends the way they are, Mac's may soon be losing their "elite" status and become much more common. Microsoft Vista is doing a great job of generating Mac converts.

A nice analogy to flawed project management practices regarding innovation: it’s like assuming that since it takes a woman 9 months to have a baby, all you need is 9 women to have a baby in a month.

A good point to remember from the (almost mythical itself) book "The Mythical Man Month." Just because you have more people doesn't mean you'll be able to program any faster, or generate ideas that are of any higher quality, or even generate more ideas. It takes quality people, quality time to come up with winners.

A couple more that don't need any comment:

Another nice project management thought: schedules are a shared hallucination.

Shouldn’t a medication that helps men stop having to go the bathroom dozens of times a day be called Flo-Min rather than Flo-Max?

Way back in the early days of my interactions with the Internet (1996), I started learning the Perl programming language. I had a client who wanted to create a database-driven web site, and before I realized I had no idea how to do that, I said, "I can do that." Well, my search (probably on the term "CGI") led me to CGI Programming on the World Wide Web by Shishir Gundavaram. Since that book used Perl, I learned Perl, my first "real" programming language (I had learned a little bit of C64/MS Basic before that).

Fast forward ten years. By now I've done a few database-driven web sites, a few C/C++ projects, and a fair bit of database design and programming (in Visual Basic). Should mean I'm a Perl hacker for life, right?

Well, maybe not. Around the end of last year, I had just completed a 500 line script in Perl that extracted data from files, and generated pages and diagnostic data. After that, I realized that I did not want to code my entire Master's project in Perl. Keeping track of the data structures became a nightmare, and I realized how much I struggled to wrap my mind around the syntax, instead of it coming naturally and efficiently. I needed something better...at least something that worked better for me.

[I pause here to note: this is not a flame against Perl. As I stated, I used Perl for 10 years, and enjoyed using it, and was very productive using it (at least in smaller scale projects). I just came up against a project and domain where Perl wasn't the best fit for me. It may very well have been the best fit for someone else. We now return to our regularly scheduled blog entry...]

I'm familiar with a lot of languages, but as stated, have only used Perl, Visual Basic, and C/C++ in any real capacity. I had heard a lot about Python, and knew enough to know that I'd probably enjoy the way it's set up. I like organization, and one of the ways Python organizes things is by using indents to denote blocks of code: all code at a particular level of indent is in the same block. An example, using classes, methods, and 'if' statements.



And there you have a fully functional python class. Python's class syntax is so intuitive to me that I've used (that is written) more classes in Python in the past few months than in all my years of Perl programming. In addition, I find the syntax to use objects in Python to be more natural, and less to type for that matter.

-- '.' instead of '->' as the object accessor. It's just easier to type.
-- Calling the class name as the constructor instead of PackageName->new() makes more sense to me.
-- Declare a class with 'class ClassName' instead of the several lines it takes to define a class in Perl

There are other reasons and areas as well where the syntax, semantics, and philosophy of Python just makes more sense for me, and I may write on those in a future post.

You can read my evaluation and reasons (complete with Typos) which I wrote for my boss and coworker to justify coming up to speed in a new programming language for my Master's/Work project.

To sum it all up, "I'm really liking and enjoying Python." I rewrote that aforementioned 500 line script, and added even more functionality, and ended up with not much more code. The language was very natural to learn, and it was very easy to come up to speed with the functions I needed. I've written about 1000 lines line python so far...I think I've hooked.

"... one of the main causes of the fall of the Roman Empire was that, lacking zero, they had no way to indicate successful termination of their C programs." -- Robert Firth

[Old, but good.]

Tonight I was reading through SourceForge's newsletter, and one of the top 25 projects is a relatively new one call ThinWire. There are a lot of existing frameworks out there for making AJAX applications look like "desktop applications," and often they allow you to dispense with programming in HTML and Javascript. Examples include Morfik, Google Web Toolkit, and even a Python version: Pyjamas. With most frameworks, while they looked good, they were often heavy (large download), or left something to be desired in the aesthetics department. Thinwire looks to change that. Take a look at their Playground Demo for examples of the full range of the tool kit, then look at their mail demo to see just how close to the "desktop feel" they get. They are even working on a graphical form designer that is written using the framework itself. Now there's power! And they claim in only a 100K download. Lest you think this is a toy framework, they also have a video showing a production application written using ThinWire. From their site:

This application has over 300 data input forms and dialogs with a wide range of complexity. It has a business rules engine that toggles the visibility of fields, required state of fields, limits dropdown options and much more....There are no page refreshes involved in updating anything within ThinWire®, the page is modified on the fly as a result of user actions that trigger event listeners on the server. Like all applications built with ThinWire®, no client-side code or HTML was written; all logic resides on the server.

One teaser that caught my eye is on their front page where they say you can develop using Java, or "alternatively, use a scripting language." I can't find further explanation of that, but if I could program in this framework using Python, I think we would have a real winner.

They are gunning for the Duke's Choice Award, so if you have experiences with ThinWire, or want to try it out, they are looking for company and developer feedback as part of the nomination process. I'll certainly be following the development efforts.

If you're starting to end sentences with semicolons try Python. My new primary language. I have a draft saved at the moment about my transition to Python. Short story: I'm loving it. Stay tuned.