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by stcredzero 2744 days ago
This might be why a lot of people (including me) hate whiteboard-coding interviews: we’ve gotten so spoiled by our tools that we can’t code without them!

Isn't that like someone saying they've gotten so spoiled by training wheels, they can't ride a bike without them? It's not like I'm one to talk 100% of the time. I think I couldn't get my company's project to build, without a few weeks of reading and understanding a lot more of the build system. However, I've also coded on an 8 bit machine by flipping 8 switches and pressing a commit button for each byte.

It's a worthwhile exercise to do some coding with nothing but a text editor and a debugger once in a while. That isn't going 100% to the bare metal, but it's a level that's very worthwhile for working on basic skills. Entire programming education books have been based on this idea.

2 comments

The difference is that training wheels are intended to be a temporary assistance until you've learned to operate without them, while development tools are meant to be a productivity boost. If you're working with a toolchain and aren't leaning on it, you're not working to your full potential.

Whether being able to work without the chain is also important is an independent issue. (I happen to prefer vim+scripting languages over IDEs+compiled. But I recognize it as a personal preference, and not a question of moral superiority.)

The difference is that training wheels are intended to be a temporary assistance until you've learned to operate without them, while development tools are meant to be a productivity boost.

Right, but pro cyclists don't say they couldn't do it without piece of equipment X. X is just a performance boost. Some coders say they couldn't practically do it at all without X. There would be a big difference in fitness between a commuter being unable to make a certain trip without a motor assist, and a rider who could do the same trip without the motor assist. I think most would look askance at a "pro" in the 1st category.

If you're working with a toolchain and aren't leaning on it, you're not working to your full potential.

Yes, but you need to be wary that you're using the toolchain for its intended purpose. The toolchain is supposed to be saving you typing and lookup time. It's not supposed to be substituting for your actual understanding of the code. The former is a good thing, and you should be good at using the tool for that. The latter is a bad thing, and you shouldn't be doing that. By working out with nothing but an editor sometimes, you can work out in a way that guards against that.

No football player plays actual games running through tires, but the exercise is apparently helpful.

But I recognize it as a personal preference, and not a question of moral superiority.

It's not moral superiority. It's using tools as intended and not substituting for understanding.

It isn't that simple.

A lot of what compilers catch are careless errors like mistyped variable names and missing semi-colons. This is not fundamental understanding of the code. This is a level of care that it is perfectly fine to let your toolchain handle for you.

A more interesting case is type checking. One of the reasons to use static type checking is that you are free to change the type of a variable or argument to a function, and then let your compiler tell you what needs to be fixed. Each individual fix is straightforward and easy - you understand it. But thanks to the toolchain you don't have to find them.

Choosing to work with dynamic typing and exercise vigilance is a reasonable choice. (In fact this is what I choose.) Choosing to work with static typing and let the toolchain help you in ways that it was designed to help is a reasonable choice. But choosing to work with static typing and refusing to take advantage of how it lets a toolchain help you is not a choice that makes sense to me.

That you should know how to operate without the tools is one thing - I strongly support it. But maintaining your practice in doing so is quite another.

Choosing to work with dynamic typing and exercise vigilance is a reasonable choice. (In fact this is what I choose.)

The biggest chunk of my professional work is still in Smalltalk.

But choosing to work with static typing and refusing to take advantage of how it lets a toolchain help you is not a choice that makes sense to me.

Yet despite being a Smalltalker for years, I'm still an advocate of static type annotation. It enables you to do more refactoring than not having it. It enables you to know sooner about incorrectly written code.

That you should know how to operate without the tools is one thing - I strongly support it. But maintaining your practice in doing so is quite another.

The "maintaining your practice" I'm advocating in this thread is merely: "Code without an IDE once in awhile to make sure you know how to operate without the tools." You don't have to fire drill every day. There is some benefit to doing it once in awhile, however.

I'm not advocating not using an IDE. I'm merely advocating for knowing exactly what it is the IDE is doing for you and doing to you. It's just wise practice for any professional power tool.

Yes, but you need to be wary that you're using the toolchain for its intended purpose. The toolchain is supposed to be saving you typing and lookup time. It's not supposed to be substituting for your actual understanding of the code.

The problem is, I don't think anyone completely understands the code when they write it. 90% of the time, you're writing code with a library written by someone else and you have an abstract understanding of what it does. That's the whole point of code is to abstract as much detail as possible. Its so you don't have to know what the machine code equivalent of X CPU add instruction is when coding a website for example. You just type + and the compiler/interpreter does everything for you.

The problem is, I don't think anyone completely understands the code when they write it. 90% of the time, you're writing code with a library written by someone else and you have an abstract understanding of what it does.

The trick is this: Do you actually have that good abstract working understanding, or have you only convinced yourself? This is the difference between sloppily convincing yourself you understand a word salad, or being able to coherently teach a concept. It's even a further step to be able to understand the specification of something in enough detail to be able to implement it and to see potential pitfalls. (This is the difference between real science and cargo cult science: Predictive Power.)

You just type + and the compiler/interpreter does everything for you.

There's a world of difference between just typing "+" or "/" because you've seen it and just going on token frequency/pattern matching, and really understanding the concept.

    X = Y + Z
Is often going to be quite different in control flow consequences from

    X = Y / Z
If Z happens to be zero.

If one is a careful programmer who has done substantive work, one should know there's a world of difference between a specification of a program that sounds good on the surface and a really good specification. After many years, one will have encountered many specifications which had to be re-thought one or more times to be practically implemented.

No, you shouldn't have to always rewire your program in hardware from NAND gates you make yourself from silicon in the bucket of sand under your desk. (I've actually quit a job because the manager was going overboard with that attitude.) But you should be able to peek under the next level of abstraction, and have enough working knowledge to become wary and know when you should be peeking. Either you can do this, or you do not have that level of skill/knowledge. Simple as that.

(Addendum: If you think to yourself that you can't do that, there's two common reactions to that. Either you tell yourself excuses and denigrate and don't bother, or you roll up your sleeves and learn it for yourself. You choose.)

There's a world of difference between just typing "+" or "/" because you've seen it and just going on token frequency/pattern matching, and really understanding the concept.

    X = Y + Z
Is often going to be quite different in control flow consequences from X = Y / Z If Z happens to be zero.

Obviously, but that is more of a concept in understanding mathematics than writing and understanding code. For example, do you need to know that Y / 0 returns a custom exception inherited from several parent classes under the parent Exception? Are you really thinking about all that when you code? Or is it mostly irrelevant and you just need to know that an error occurs and you need to be mindful of it (regardless of whether the error comes in the form of an exception, error code, hardware interrupt, etc.)

API's are written specifically to avoid needing to peek under the code and you should only really need to if they are poorly documented. Even then, you only seem to think only the next level of abstraction is warranted and not other levels (i.e. IL/x86 assembly or machine code). This next level of abstraction can yield important learning in code optimization because what you write in a higher level language can be implemented in multiple ways at a lower one (sometimes at a performance determent).

Either way, most coding is a black box exercise. While looking under the hood is useful and informative at times, nobody has the brain capacity nor time to absorb it all and apply it. Which is why the smart people built upon other smart people to put a model in place that can be applied without knowing what machine instructions your computer spits out after compilation, or without knowing the implementation details of how you get a list of a specific type or how it adds/removes/copies/etc. Same as science. You don't need to do an experiment every time to know the motion of the planets, measuring their positions in the sky each time to calculate the orbits and deriving the equations through calculus. You simply skip to the step of Newtonian mechanics and kinematic equations.

Imagine if everyone had to learn how an engine worked in order to operate a vehicle. Hardly anyone would be able to drive.

Obviously, but that is more of a concept in understanding mathematics than writing and understanding code. For example, do you need to know that Y / 0 returns a custom exception inherited from several parent classes under the parent Exception? Are you really thinking about all that when you code?

Indeed. In a conversation like this, the mention of divide by zero is just supposed to evoke all of that for an audience of programmers.

API's are written specifically to avoid needing to peek under the code

Any product is designed to be simply used. The difference between an end user and a pro is that the pro can sometimes go a little further and sometimes needs to because they can push the product harder.

Either way, most coding is a black box exercise.

As is most professional activity of any kind. Most of any job is kind of routine. That's why they call it "routine." What distinguishes the consummate pro is the ability to go beyond when needed.

While looking under the hood is useful and informative at times, nobody has the brain capacity nor time to absorb it all and apply it. Which is why the smart people built upon other smart people

Being a smart person means taking into account context and getting the best cost/benefit. Nobody who is "smart" would advocate knowing absolutely everything about everything, all the time. That's clearly a straw man. (Perhaps you are pressing things in a certain direction?) It's also clearly not the position I'm advocating for. Likewise, nobody who's smart would simply advocate for ignorance. Not even the smartest people are infallible. Smart people are simply prepared for when things go wrong.

Imagine if everyone had to learn how an engine worked in order to operate a vehicle. Hardly anyone would be able to drive.

Funny you should mention this, but I was about to bring up that analogy, then decided to leave it off. I guess you're indicating it should be brought up. A typical driver doesn't need to know much about their engine. However, a professional driver of one of several different types is very well served by some knowledge of engines. Such knowledge isn't needed all the time, but when it is needed, the potential costs of not knowing can be quite high. You could lose a race, lose money, or lose a life.

It's like a lumberjack so used to cutting down trees with a chainsaw that they'd have trouble to put down a decent tree with an axe. Powerful tools do certain subtasks for you, if you expect to use them all the time (and it's a reasonable expectation in your domain), then it makes all sense that you'd forget these subtasks.

It's like manual memory allocation and proper deallocation - been there, done that, but after 10+ years of working with GC languages, I would definitely have some memory leak bugs if I suddenly had to do that again. It is a basic skill, but just as many other basic skills, it's one that you can ignore in most domains.

It's like a lumberjack so used to cutting down trees with a chainsaw that they'd have trouble to put down a decent tree with an axe.

Bad analogy. It's more like a "lumberjack" who thinks all it takes is pressing the controls on a chainsaw. There's some more, very important things to know, and not knowing them can cost time and money or even get someone badly hurt. The chainsaw has to be maintained, with possibly severe consequences if it isn't. You need to know how to get the tree to fall where it's supposed to. You have to know how to cut so the weight of the tree doesn't clamp the chain.

It's a bad analogy, because the important issue is whether someone is letting the tool substitute for understanding. I guess some rube might think their chainsaw is so powerful, they don't have to worry about how they cut down the tree. It's more like sailors who think they can just lean on GPS instead of having skills. Those are the guys who collide their ships and get people killed. It's more like pilots who weren't great student pilots, and they make critical mistakes and program the autopilot into the side of a mountain or do the wrong thing when the plane is stalling or always depend on the auto-landing system and don't really know how to do a manual landing and wreck the plane. (Those are all things that really happened.)

Just because some big fraction of time being a "professional" is just being an end user doesn't mean there isn't something more beyond that which is very important. I guess it just has to do with what level of "professional" you aspire to be.

It's like manual memory allocation and proper deallocation - been there, done that, but after 10+ years of working with GC languages, I would definitely have some memory leak bugs if I suddenly had to do that again. It is a basic skill, but just as many other basic skills, it's one that you can ignore in most domains.

If you're doing something hard enough, you still have to think about stuff like that in a GC environment. I know, because I worked for a Smalltalk vendor. You can even have memory leaks in a GC environment. There's a lot of stuff you can ignore -- most of the time -- but can come and bite you real hard if you're not prepared for it.