Programmers - Poets or Mathematicians?

Programming software is much like writing a story. Any given story can be told in a near-infinite number of ways and those who practice the craft will spend just as much time, if not more, arguing over the style of a work, as if their subjective opinion can suddenly become objective fact. Usually this leads to a contest of "If you don't agree with me, I'll just keep talking until you see reason" or otherwise known as talking the subject to death.

I thought I'd shine some light on an example of this issue in programming. There is a never-ending debate in programming circles about the 'proper' way to write code that creates some true/false decision. Stackoverflow has a good example of this.

My personal pet peeve (petty but my teeth grind everytime I see it) is verbosely setting booleans, e.g.

bool isValid;
if (percentage >= 0 && percentage <= 100)
   isValid = true;
else
   isValid = false;

whats wrong with

bool isValid = percentage >= 0 && percentage <= 100;

It's soooooo much more succinct and easier on the eye

Even though the single line version isn't the most complex, different people read through code in different ways. A single expression can be easily parsed by people who have a math background or are experienced coders. That's not the point. The expanded version reads more like a sentence than a formula. It's easy to forget that there are plenty of coders without a background in math. It really comes back to the preferred style of the reader. Do they prefer reading expressions and formulae or something more like human speech.

Homer's The Illiad and The Oddessy are ancient works dedicated to expressions of speech. They were originally poems that were passed down in an oral tradition and meant to be sung instead of read.

Euclid's Elements is a work dedicated to expressions of logic. It covers objective proofs and unambiguous facts and is the beginning of the mathematical tradition, if you will, of rigorous scientific thinking.

The problem we face in software is code is a form of human expression, with all the imprecision that entails, attempting to communicate with the utterly logical CPU; programmers will be forever trying to translate "An Ode to the Machine" into the Pythagorean Theorem.

If Gulliver Were a Designer

The term 'Design' gets thrown around a lot in software developer circles. There are constant flamewars over favorite techniques and battles over what good design really entails. When those arguments start getting too ad hominem figure out whether the speaker is a Code Monkey before giving them much credence. Since I've already braved the waters, see "Have Design Will Travel" or "The Age of the Design Review", instead of safely avoiding the issue, I'm going to bravely (or foolishly) join the fray.

Realize that there is more than one type of 'Design'. Design in the large turns into architecture and is something that really only comes with experience. Designing at the lower levels, say at the individual class/object level is easier to cover. Today I'm writing about design in the small vs the large; Lilliput vs. Brobdingnag.

The issues with designing a class is the same regardless of platform or language. The key is whether an object should be autonomous or whether it is better for any given behavior to be spread out among objects with limited scope and distributed responsibility.

For each class the answer might be different. We end up with a spectrum along which we can place classes based upon the Density of Responsibility.

             (Level of responsibility for behavior)
        Autonomy - - - - - - - - - - -  - - Dependence
     High
 C      -   [god object]                [spaghetti]
 l      -
 a      -
 s      -                                
 s      -           
        -                  
 s      -
 i      -
 z      -
 e      -  [template]                   [framework]
      low

Let's say you favor letting the class perform all the behaviors itself, or as many as you can. Starting on the left side of this graph, when you make your class more autonomous, the size of the class will grow unless you continuously refactor it to make it more generic. This leads to a template. If no refactoring is done, the tendency is for the class to become more "god-like" because if there is some behavior it needs, it has a method for that - it can do anything and everything. The number of fields and methods grow and soon become both unmanageable and unavoidable. Since the class already does so much, coders would rather add to the monstrosity than try to piece it apart and cut the Gordian knot.

The right side of the graph has classes that depend on other classes to a large degree. If the dependency level is high but the individual class is small, that is a sign of a framework; each class doesn't do much and requires lots of dependent classes to accomplish some function. On the other hand, a highly-dependent class that also has a large amount of code is a sign that the class is full of spaghetti.

The key to this question is to determine where you feel more comfortable on the graph. In any event, individual classes will end up spread out on the graph unless some organizational principle is applied, which is how you can achieve the results of Template or Framework.

Having just written that, I would say that there is a correlation between class size and degree of organization. Robert C. Martin (or "Uncle Bob") covers similar ground with package dependencies in his very thorough paper on Design Principles and Design Patterns[pdf]. JDepend is an implementation of the ideas behind the graph on page 26 and complements static analysis tools such as Checkstyle and PMD.

Extreme Programming is People

There has been an enormous about written in the blogosphere on ways to improve how we write software. Much of the virtual ink spilled on the Internet about Extreme Programming, or Agile, or SCRUM, gathers at opposite ends of the spectrum. Some focuses on how those practices make things better, usually in a overly enthusiastic way which invites the curt dismissal as nothing more than hype and hyperbole. Others constantly remind everyone that they've tried it and it didn't work which invites observations about anti-social programmers.

Both camps need to call a truce. They'll get much farther - and be happier - if they stop throwing grenades at each other and start talking to each other.

We can get both sides to agree that the previous ways of software development is problematic and certainly non-optimal, at least if the goal is to develop acceptable software in a reasonably quick, consistent, and effective manner.

Once we've agreed on common goals, we can discuss typical obstacles and plan ways to avoid or mitigate them. One of the biggest problems, and least discussed, is how people affect the processes in which they participate. There is a good article by Alistair Cockburn about this phenomenon. His paper is titled "Characterizing people as non-linear, first-order components in software development".

The Story of Joe and Al

So let's examine more of the laws and how they affect an effort to introduce Extreme Programming. People who use the 48 Laws as a handbook for how to live their lives are usually label as evil, justifiably so. I don't want this discussion to degenerate into name calling or dismissed because of guilt by association so let's create two personas as our antagonist and protagonist. We'll call the willing and manipulative one Joseph (think Stalin) and the unwitting and hapless one Al (think Flowers for Algernon).

Law #1 "Never Outshine The Master". Humans are sensitive about losing face in front of others. Joseph uses this to his advantage to keep from attracting the wrong kind of attention. Al is proud of his achievements and doesn't understand why others don't share in his celebration.

Law #2 "Never put too Much Trust in Friends, Learn how to use Enemies" - Joseph keeps reminding himself to watch out for number one. He doesn't want to put his fate into the hands of others which means fewer allies but also fewer fair-weather friends. Al, on the other hand, cannot comprehend the idea that people have hidden motives even while having repeated instances of being taken advantage of.

Law #3 "Conceal your Intentions" is "Do unto others before they have a chance to do it to you". Keep the knife hidden from your intended victim. Joseph believes that life is a zero-sum game. Since he values himself over all others, he won't lose any sleep taking what he wants so he'll have more. He's interested in power and control, if he takes it from you it means you'll be powerless to respond after his power grab is fate de'compli. Al doesn't have the mental capacity to think one thing while saying or acting another. George Orwell's "Doublespeak" would be a foreign concept.

Law #7 "Get others to do the Work for you, but Always Take the Credit". Some poor soul on StackOverflow called this a "Seagull Manager - a scavenger who takes all the credit for your hard earned work and hangs around you like a bad smell." This will be a common behavior for Joseph who lacks scruples and thinks those who let him get away with it deserve to have their credit stolen. Al believes what society preaches in public, the value of hard work, work hard and keep your nose clean and you'll get what's coming to you, etc. He has the pride of the workman where good work will be recognized and rewarded. Combine that with no ability to detect deceit in others and you end up with someone who becomes the pawn of others. Naively believing the promises of their antagonists.

You can't approach a social situation as if everyone has the same motivations. Workplaces have plenty of Josephs blending in waiting for any situation to turn to their own personal advantage, and Algernons trying in vain to be accepted. If we don't recognize that, we'll be like farmers watering their crops with beer, "It tastes good to me so it must also be good for growing corn."