>> The abstraction is just barely enough to get the job done [...]
> Or, in other words, the perfect amount...
Well no, because the job doesn't end when it's "done". Minecraft is the perfect example:
In the earliest versions of the game, blocks were all basically homogenous cubes of some material, so they didn't need to be oriented. Later, blocks were added that did need to be rotated in various ways, e.g. torches, stairs. But each of these blocks had their own private system for choosing, storing, and rendering their orientation. These systems were often similar, but not identical. At this point, roughly half the blocks in the game are orientable in some way and there is still no generic orientation system. Such a system would have avoided massive amounts of redundant code, prevented many bugs, made the user experience more consistent, and made various 3rd party tools much easier to develop.
"You ain't gonna need it" is a cop-out. You are going to need some things. The trick is anticipating which things, and it will definitely pay off if you can guess correctly.
Hmm, from what I can tell, Minecraft is fairly successful, despite it being a "perfect example" of not having enough abstraction.
Of course, you fail to really acknowledge the risks of premature abstraction. Sure, if you could see the future, and know what patterns could be usefully factored out into abstractions, it would be good to start with those abstractions. But what happens if you incorrectly predict that an abstraction will be needed? You create a bunch of unnecessary framework code that is harder to understand, likely less efficient, and worst of all, you wasted time writing code that you didn't need.
YAGNI is not a cop-out. The best way to create abstractions is from concrete examples. Write something once. Then, once you actually find yourself writing it twice, abstract it out. That guarantees that you don't waste time on things that you don't use. It also generally leads to better abstractions, because you have concrete use-cases to work from.
Anyway, back to the Minecraft story, who are you to say that the game would be better if Notch followed the premature abstraction strategy? Isn't it possible, perhaps, that he would have wasted enough time implementing ivory towers of abstraction that he might have left out the features that actually made the game fun?
But what happens if you incorrectly predict that an abstraction will be needed?
Then you made a mistake and hopefully learned something. I didn't say architecting software was easy or without risk, just that you can't avoid doing it by following simplistic rules.
The best way to create abstractions is from concrete examples. Write something once. Then, once you actually find yourself writing it twice, abstract it out.
It's nice when things go that way, but it's not the general case. Often, by the time there is a concrete use for abstraction, the damage is done. For example, adding network multiplayer to a game that has been architected for single player is a nightmare of hacks and duplicated code (Notch has explicitly lamented about that one).
Anyway, back to the Minecraft story, who are you to say that the game would be better if Notch followed the premature abstraction strategy?
Notch himself seems to be saying as much in that blog post. But that aside, I'm a fellow game developer who has spent dozens of hours reading and modifying the Minecraft code. Even after a round-trip of obfuscation, it tells the story of its creation quite vividly, and the theme of the story is "hack around it!" Though I still have tremendous admiration for the game and its developers.
I think the point was that the source code doesn't make the game better or worse.
A nightmare of hacks is fine as long as the product is great.
IMO writing such code is sometimes even better, especially for a solo developer. If you aim to write beautiful code, it might eventually outweigh everything else, while giving a false impression that you're doing the right thing. Your goal is the product, not code. I'd argue that you can't focus on both (it's called ‘focus’ for a reason).
Of course source code makes the game better or worse. The game is made of code. The code makes the game what it is.
If you write good code, your product will work better and be done sooner. This is the definition of good code. If you write bad code, your product may be overbudget, buggy, inadequate, and so on. This is the definition of bad code.
There is no dichotomy between the product and the code. To suggest that you can make better software by neglecting the code is absurd.
No arguing with that. Same as building material makes a house what it is. The question is, does the success depend on material used? You can build a great house amidst the desert.
But that's an analogy. More real-world example—imagine two startups:
- Startup 1: bad programmer, good QA.
- Startup 2: good programmer, bad QA.
Where would you invest your money?
> If you write bad code, your product may be overbudget, buggy, inadequate, and so on.
Here I disagree. Overbudget? It depends on product success. Buggy? If you have good QA, it's not buggy. Inadequate? You can write the cleanest code, but your product won't work as users want it to.
When we say ‘great product’, do we mean that it has nice clean code, or it's something else? How many great products have bad code?
> There is no dichotomy between the product and the code.
As long as you are ‘just a’ developer, and there are other people focusing on product and its functional quality. In that case you receive specific tasks with deadlines, and yes, you should focus on writing good code.
Not so if you're a solo developer.
1) No one will focus on the product, except you.
2) You most likely would be heavily biased towards writing good code. (Because you're a developer, you're supposed to write good code, right?)
You need to force yourself to focus on the product, to avoid becoming the Startup 2 from above example. Intentionally writing bad code is one way to do that. In that case you at least can be that Startup 1—you'll be forced to pay more attention to functional quality (as opposed to structural), so you'll be good QA.
You can argue that one can focus on both. My opinion is that it's too risky. You need to have priorities set as clear as possible.
> To suggest that you can make better software by neglecting the code is absurd.
Yes, it sounds really controversial (especially to a programmer). I'm far from satisfied with that statement. What would be a better way to be a good QA while being a great programmer?
Multiplayer mode can be extremely hard and can take any fun out of being an indie game developer. I'm still not sure if it is the right abstraction to work in on day one.
"""Well no, because the job doesn't end when it's "done"."""
By definition, it does.
"""In the earliest versions of the game, blocks were all basically homogenous cubes of some material, so they didn't need to be oriented. Later, blocks were added that did need to be rotated in various ways (...)"""
So you are suggesting that they should have set up a system to allow that from the beginning.
Have you sat and thought how adding things like that could delay the initial release?
Also, have you sat and thought that if the initial release was not successful at the marketplace, all that extra work would have been in vain?
[downvote? Thanks, parent]
Just build what you need at the time, and make it flexible enough so that it can be refactored to something else later.
Philosophically, I agree. I view premature abstraction in the same light as premature optimization. I believe both abstraction and optimization are incarnations of your understanding of the problem. You want them in important places, not necessarily everywhere, and hence you want them late enough in the engineering process that you understand which places are important.
That said, within the comfort zone, there are high and low levels of abstraction. For example, in a project the size of Minecraft, I would expect CS major code to contain an ObjectFactoryFacadeCollection or two. Minecraft has nothing of the sort. It sticks almost exclusively to the Mob::HostileMob::Zombie inheritance we all grew up with. This is not bad or good[1], it's simply a reflection of the low-abstraction style of attacking problems that I associate with self-taught programmers.
On the other hand, its Magic Number to Constant ratio is downright scandalous . . . ;) Though it's possible that some of that is an artifact of the compilation/decompilation process.
Have you ever looked at a class named ObjectFactoryFacadeCollection and thought to yourself, "oh boy, this part will be fun to read?"
On one hand there's the complexity of the problem you're solving. On the other hand, there's incidental complexity. The ObjectFactoryFacadeCollection class squarely falls into the incidental complexity category. In other words, the moment you are writing a class of that sort, you have stopped working on solving the problem you set out to solve -- you're solving a problem that was invented by your tools, design, or limits of your understanding.
This isn't necessarily true. Sometimes you do in fact need these types of abstractions. This is why they've been made into patterns. The trick is to not use it before its necessary. The mere existence of it doesn't imply overengineered code.
Yes, of course you do sometimes need these types of abstractions, but you seem to have missed my point: they are a factor of incidental complexity. To restate, they are not at all inherent to the problem you are trying to solve. They are inherent to the tools with which you are solving the problem.
For instance, if your problem is calculating the trajectory of a projectile, a solution certainly exists that does not involve anything at all like an ObjectFactoryFacadeCollection. However, certain solutions involving unnecessarily complex abstractions could conceivably require one. This is incidental complexity. On the other hand, all solutions will require some information about the projectile's velocity, gravity, and so forth. This is complexity that is inherent to the problem itself.
Philosophically, I agree. I view premature abstraction in the same light as premature optimization.
It's usually easier to optimize later since optimisations are often just taking sections of code independantly and making them quicker. There is the whole 90/10 rule (or whatever it's called) that says it's better to highly optimise a few sections of bottleneck code rather than the whole thing.
Trying to retrofit an abstraction to a piece of code is almost always a horrible experience frought with mess and compromise.
Trying to retrofit an abstraction to a piece of code is almost always a horrible experience frought with mess and compromise.
Yes, and unless the problem is trivial or your experience in the domain is such that your foresight borders on the clairvoyant, this is guaranteed to happen. No matter how much (or little) design you do up front.
The key is to recognize the right time to stop and refactor, so as to keep the pain that comes with learning the problem space to a minimum.
Premature abstractions can have similar issues: unless you have more than 2 cases you don't necessarily know what your abstraction should look like. As the cases pile up you find yourself increasingly shoehorning implementations into abstractions that don't quite abstract correctly.
> Trying to retrofit an abstraction to a piece of code is almost always a horrible experience frought with mess and compromise.
It is amazing to me that our experiences are so different: I have found the exact opposite of this statement to be true. The only way that I've ever come up with a good abstraction is by starting with something concrete (preferably two or more instances) and factoring out the commonality. Retrofitting a piece of code to an abstraction that was designed in a vacuum tends to be an exercise in frustration, due to the abstraction being shortsighted and insufficiently suited to the problem space.
A well-abstracted program can be easier to optimize because modules are more loosely connected and their internal implementations can be replaced/optimized without breaking the rest of the code.
I disagree. Abstraction is fundamental to programming. The more abstractions, the better. I'm not talking about design patterns here, but abstractions that hold explanatory power in your problem space. They necessarily increase code comprehension, reduce potential bugs, etc.
Abstractions reduce potential bugs by reducing the 'interaction-space' of a particular entity in your code. Think about a program that has 100 variables all in one function. That is potentially 100! interactions between entities in your code. When you make a change, you have to reason about all 100! interactions to be sure you're not introducing a new bug.
Abstracts greatly reduce this space. If instead you have 10 objects who each contain 10 variables, within the object you have 10! interactions to reason about. In the main function that ties each object together you now have 10! interactions to reason about. This is many many orders of magnitude easier than the original problem.
The more (natural) abstractions, the better your code.
No. A hundred times no. If you have ever had to make sense of a complex program that was over-engineered with unnecessarily complex abstractions, you cannot possibly think that this is true.
> Think about a program that has 100 variables all in one function [...]
This isn't an example of code that is not abstract enough, it's an example of a basic failure to understand the principles of writing a program meant to be read by other humans. Sure, breaking that code up into understandable chunks is a form of abstraction, but it's not exactly the kind of abstraction that the grandparent was talking about. She was talking about "extremely elaborate object frameworks." I maintain that elaborate object frameworks are a bad thing, unless they are "barely enough to get the job done." Anything beyond that adds unnecessary complexity.
This beautiful and poignant quote sums things up much better than I ever could:
“Perfection is achieved not when there is nothing left to add, but when there is nothing left to take away” – Antoine de Saint-Exupery
He may have been referring to framework-level abstractions, but I was specifically referring to natural abstractions for the problem space. Blanket statements against abstractions in code is missing the point--abstractions are fundamental to programming. "Elaborate object frameworks" could mean a few different things. If you're referring to design pattern type structures, then I somewhat agree that the fewer the better. But in the general case it is not true that perfect is not being able to take anything more away. Not when humans are the ones writing and maintaining the code.
Abstractions reflect a persons understanding of the problem space. Iterative game development is exploratory. There is some trade off between redundant code and ease of local modification without worrying about global impact.
In my experience as a person who has been hired before, I can say that I would absolutely prefer well-factored, but rather concrete code over towering abstractions. Sure, if something is a general feature, it should be abstract. There's nothing more frustrating, though, than wading through layers of abstractions, only to find that hidden behind them is a singular concrete implementation.
Well, I would have called you on this, but I guess I don't have to.
> The abstraction is just barely enough to get the job done [...]
Or, in other words, the perfect amount...