A while ago, I had an insight that proved intellectually fruitful. I think that within this idea is a seed of much more to come.
The insight is this: There are, fundamentally, two separate phases to learning to program. The first phase is learning the mechanics of getting a program to work. The second phase is learning to make a program that is comprehensible, useful, and extensible.
remember most about learning it was the difficulty I had in
understanding basically every single idea. Because I had learned
HTML, I understood the idea of syntax. I also understood
statements, but a
for loop was beyond me. Forget about
prototypical-inheritance -- I was baffled.
I did, however, get over this stage. At some point I learned PHP, and began to grasp how this stuff worked. I hit a pretty good point where I was able to build things without that much difficulty.
The first program that really threw me was a project I was working on in C. Segmentation faults were really common, of course, which made things difficult. However, this program got to the point where it was incomprehensible.
This, I think, was my first taste of the second phase of programming -- that is, making your code make sense. I eventually abandoned that project (it was really just a learning exercise anyway), but the lesson stuck with me.
While this story is specific to me, I have heard similar things from other programmers in the past. It makes sense: We start out unable to get the computer to do anything. Then, once we know how to make a computer do what we want, we quickly build incomprehensible, unmaintainable piles of code.
Of course, the first concern never goes away. Just because we have learned to make computers do things does not mean programming is always easy. And, obviously, the second phase is still around. Who can say that they truly always write "good code", code which doesn't need replacing eventually for sheer wrongness? I don't know of anyone who would say that about themselves.
I am sufficiently confident to say that I do think that this properly describes the way things /are/, but it does not describe /why/ they are that way. What is more, we (generally) know how to make our code more "correct" in the it-does-what-I-want way, but we still don't know how to structure our code particularly well.
We have a number of tools available that can make us write code that works better. The most basic is education. Learning more about the systems we work with gives us the foresight to anticipate what problems may arise with the system. Test Driven Development has done so well over the last decade because it also allows us to have way more confidence in our code. Potentially, we could even go so far as to logically prove that our code behaves correctly.
However, the second area is more difficult. For given problem, how should you architect its solution? Would a functional approach, procedural approach, or object-oriented approach be best? Or, could we go with an even more less-common, logic-oriented solution?
We do know how to make some judgments though. For example, smaller classes tend to be better than large classes. Small, direct functions are better than large ones. Code duplication is bad. These aren't always really right, though.
So, why is this second task -- the task of structuring code in the right way -- so very difficult? If you have any insights, let me know!