I use what I learned from watching a talk by him on clean code and I had to learn some stuff. It might be “common sense” for experienced developers. But it certainly doesn’t come naturally that “functions should do one thing” to first time coders. The thought processes of when the software was developed usually isn’t the best way the code should be structured in the end. But that’s usually how beginners code.
It’s mostly based on what he feels is good.
In most diciplines, experience in the field is what makes the knowledge of the field. You don’t always have to be able to explain why good practice does what it does.
Also: I know of some examples, where he clearly explains his reasoning, e.g. why comments shouldn’t explain how the code works. (Because they’re not going to be updated, when the code will be)
As a programmer, I want all relevant logic of a method to be neatly collected in one place - not scattered around deeply nested method calls.
Either you misrepresent him, or you get a hard nope from me. Staying on one layer of abstraction is most likely my most important principle of writing understandable and maintainable code.
One of my main issues is, seeing his code in the past decade… It feels like this guy hasn’t coded in a collaborative environment in years.
His personal opinion tends to get on the way with code that’s easier to read from a team perspective. And “Uncle Bob” pushing that as the defacto way to code.
This happens from Influencer types who are so detached from the industry for decades and are no longer aligned with problems real engineers hit.
It’s not that he’s wrong. It’s that his perspective is outdated.
I categorize this as one of the better points of the book.
functions should do one thing
I kinda disagree with him on this point. I wouldn’t necessarily limit to one thing, but I think functions should preferably be minimal.
Throughout his examples he’s also using ideas like how functions should only be 3 lines long, preferably have no arguments, and also no return values.
This style of coding leads to programs that are nightmarish to work with. The relevant code you’re looking for might be 10 layers deep of function calls, but you don’t know where. You’re just jumping between functions that does barely nothing until you find the thing you’re looking for, and then you need to figure out how everything is connected together.
I prefer when things are flatter. This generally leads to more maintainable code as it’s immediately obvious what the code is doing and how everything is connected.
I think his book is the equivalent of a cleaning guide where all the steps are just to sweep all the mess under the carpet. It looks cleaner, but it’s not clean.
I kinda disagree with him on this point. I wouldn’t necessarily limit to one thing, but I think functions should preferably be minimal.
I do actually agree with him on that point - functions should do one thing. Though I generally disagree on what one thing is. It is a useless vague term and he tends to lean on the smallest possible thing a thing can be. I tend to lean on larger ideas - a function should do one thing, even if that one thing needs 100s of lines to do. Where the line of what one thing is, is a very hard hard idea to define though.
IMO a better metric is that code that changes together should live together. No jumping around lots of functions or files when you need to change something. And split things out when the idea of what they do can be isolated and abstracted away without taking away from the meaning of what the original function was doing. Rather than trying to split everything up in to 1-3 line functions - that is terrible advice.
Yeah, that’s an argument of semantics. I agree with you.
What I believe is that functions should do exactly what they advertise. If they do the things they’re supposed to do, but also do other things they’re not supposed to do, then they’re not minimal.
But I feel like Uncle Bob is leaning more towards that if a task requires 100 different operations, then that should be split into 100 different functions. One operation is one thing. Maybe not exactly, but that’s kind of vibes I get from his examples.
But I feel like Uncle Bob is leaning more towards that if a task requires 100 different operations, then that should be split into 100 different functions. One operation is one thing. Maybe not exactly, but that’s kind of vibes I get from his examples.
Oh yeah he defiantly does. He even says so in other advice like a function should be about 1-3 lines. Which IMO is just insane advice.
Yeah. I get more of what you’re saying now. The 3 line functions on principle are indeed a bit much. Although I’ve found that sometimes theare necessary to stay consistent with the layers of abstraction (e.g.: a for-loop that writes some data over some bus).
I almost pulled my hair out when I read that section. One is super obvious without any prior experience with the code. The other is an obscure abomination only he can understand. He’s obviously super proud of his abomination and thinks it’s a prime example of “clean code”.
In C# I’m using Verify - So I prefer to just use Verify(state); and compare the entire state against a json saved state, instead of manually verifying every individual property
Regarding the experience thing, I’d like to point out that a lot of us have experience that says „clean code” is a real pain in the ass to work with and think through.
You do? I have the opposite experience: I regularly stumple over dirty code where levels of abstraction differ wildly and I regularly lose my train of thought, because some function writeToFile() all of a sudden shifts some bit in a register with an outdated comment next to it (overly dramatizised).
Functions never being longer than 4 lines goes, too far IMHO, but the “clean code should read like prose” bit is something that has been really useful to me.
Functions never being longer than 4 lines goes, too far IMHO,
That’s the problem with the book! People experienced enough to sort out bad advice from it are already experienced enough to have learned the good advice.
Im not saying every word of it is wrong, just that the sum total of all his advice is. I don’t think there’s any school of thought that says it’s good for a function named ‚writeToFile’ to be doing other stuff
My (poorly chosen) example wasn’t about the side effects, but rather about the differing layers of abstraction. Almost all criticisms I’ve seen was about the “functions should be like only 4 lines” rule. Which admittetly: Is a bit whack. But no one actually pulls that rule through, do they?
I think the focus on short, simple functions combined with DRY code leads to many early, poorly chosen abstractions. Getting out from under a bad abstraction can be painful.
But no one actually pulls that rule through, do they?
They do though. Loads of new people to programming read that book and create unreadable messes of a code base that follow all of his advice. I have lost count of the number of times I have inlined functions, removed layers of abstraction and generally duplicated code to get a actual understanding of what is going on only to realize there is a vastly simpler way to structure the code that I could not see until all the layers and indirection are removed. Then to refactor again to remove redundant code and apply more useful layers again that actually made sense.
And that is the problem we have with his book. People that need it take up as many bad habits as they do good ones leading to an overall decline in their code quality. It is not until years of experience that you can understand the bad bits and ignore them. So overall his book is a net negative on the programming world. Not all his advice is bad, but if you can tell that then you likely don’t need his advice.
But on the layers of abstractions specifically, he takes this too far. Largely because of the 4 line limit he has. There is a good level of abstraction and I generally find more than 2 or 3 levels of abstraction is where I start to loose any sense of what is going on. He always seems to jump on abstraction as soon as he can, but I find waiting a while and abstraction when you need to to lead to fewer and vastly better layers of abstraction overall.
And adding more abstraction does not help the people of people doing too many things inside a function - they just move it to sub functions rather than extracting the behavior for the caller to deal with. I have never seen him give advice on what that is appropriate, only keeps the functionality of the original function the same and move the logic into a nested function instead and that only covers up the issue of the function doing too much.
Sorry, I still don’t really get the hate.
I use what I learned from watching a talk by him on clean code and I had to learn some stuff. It might be “common sense” for experienced developers. But it certainly doesn’t come naturally that “functions should do one thing” to first time coders. The thought processes of when the software was developed usually isn’t the best way the code should be structured in the end. But that’s usually how beginners code.
In most diciplines, experience in the field is what makes the knowledge of the field. You don’t always have to be able to explain why good practice does what it does.
Also: I know of some examples, where he clearly explains his reasoning, e.g. why comments shouldn’t explain how the code works. (Because they’re not going to be updated, when the code will be)
Either you misrepresent him, or you get a hard nope from me. Staying on one layer of abstraction is most likely my most important principle of writing understandable and maintainable code.
One of my main issues is, seeing his code in the past decade… It feels like this guy hasn’t coded in a collaborative environment in years.
His personal opinion tends to get on the way with code that’s easier to read from a team perspective. And “Uncle Bob” pushing that as the defacto way to code.
This happens from Influencer types who are so detached from the industry for decades and are no longer aligned with problems real engineers hit.
It’s not that he’s wrong. It’s that his perspective is outdated.
I categorize this as one of the better points of the book.
I kinda disagree with him on this point. I wouldn’t necessarily limit to one thing, but I think functions should preferably be minimal.
Throughout his examples he’s also using ideas like how functions should only be 3 lines long, preferably have no arguments, and also no return values.
This style of coding leads to programs that are nightmarish to work with. The relevant code you’re looking for might be 10 layers deep of function calls, but you don’t know where. You’re just jumping between functions that does barely nothing until you find the thing you’re looking for, and then you need to figure out how everything is connected together.
I prefer when things are flatter. This generally leads to more maintainable code as it’s immediately obvious what the code is doing and how everything is connected.
I think his book is the equivalent of a cleaning guide where all the steps are just to sweep all the mess under the carpet. It looks cleaner, but it’s not clean.
I do actually agree with him on that point - functions should do one thing. Though I generally disagree on what one thing is. It is a useless vague term and he tends to lean on the smallest possible thing a thing can be. I tend to lean on larger ideas - a function should do one thing, even if that one thing needs 100s of lines to do. Where the line of what one thing is, is a very hard hard idea to define though.
IMO a better metric is that code that changes together should live together. No jumping around lots of functions or files when you need to change something. And split things out when the idea of what they do can be isolated and abstracted away without taking away from the meaning of what the original function was doing. Rather than trying to split everything up in to 1-3 line functions - that is terrible advice.
Yeah, that’s an argument of semantics. I agree with you.
What I believe is that functions should do exactly what they advertise. If they do the things they’re supposed to do, but also do other things they’re not supposed to do, then they’re not minimal.
But I feel like Uncle Bob is leaning more towards that if a task requires 100 different operations, then that should be split into 100 different functions. One operation is one thing. Maybe not exactly, but that’s kind of vibes I get from his examples.
Oh yeah he defiantly does. He even says so in other advice like a function should be about 1-3 lines. Which IMO is just insane advice.
People can take the “do one thing” argument too far. I’ve seen people have individual micro services for each CRUD action on a resource.
This, but with separate services for read and write operations and another for event handling.
also, the dependency inversion thing makes it so that not even the tooling can help you with that, to put the cherry on the cake
Yeah. I get more of what you’re saying now. The 3 line functions on principle are indeed a bit much. Although I’ve found that sometimes theare necessary to stay consistent with the layers of abstraction (e.g.: a for-loop that writes some data over some bus).
Which of these do you prefer?
A?
@Test public void turnOnLoTempAlarmAtThreshold() throws Exception { wayTooCold(); assertEquals(“HBchL”, hw.getState()); }Or B?
@Test public void turnOnLoTempAlarmAtThreashold() throws Exception { hw.setTemp(WAY_TOO_COLD); controller.tic(); assertTrue(hw.heaterState()); assertTrue(hw.blowerState()); assertFalse(hw.coolerState()); assertFalse(hw.hiTempAlarm()); assertTrue(hw.loTempAlarm()); }Uncle Bob's Clean Code suggests
Option A
I almost pulled my hair out when I read that section. One is super obvious without any prior experience with the code. The other is an obscure abomination only he can understand. He’s obviously super proud of his abomination and thinks it’s a prime example of “clean code”.
It’s also a good example of how being too dogmatic about function length can hide important details.
Why in the holy mother of rust is A the better option?
His idea is that it’s faster to read that short string once you learn how to read it. But then you need to learn how to read it.
In my experience, every time I thought of something clever like this, I’ll almost always regret it a month later when I revisit the code.
Ask “Clean” Coders I guess lmao. Beats me.
I’ve started to prefer option A to be honest.
In C# I’m using Verify - So I prefer to just use
Verify(state);and compare the entire state against a json saved state, instead of manually verifying every individual propertyRegarding the experience thing, I’d like to point out that a lot of us have experience that says „clean code” is a real pain in the ass to work with and think through.
You do? I have the opposite experience: I regularly stumple over dirty code where levels of abstraction differ wildly and I regularly lose my train of thought, because some function
writeToFile()all of a sudden shifts some bit in a register with an outdated comment next to it (overly dramatizised).Functions never being longer than 4 lines goes, too far IMHO, but the “clean code should read like prose” bit is something that has been really useful to me.
That’s the problem with the book! People experienced enough to sort out bad advice from it are already experienced enough to have learned the good advice.
Im not saying every word of it is wrong, just that the sum total of all his advice is. I don’t think there’s any school of thought that says it’s good for a function named ‚writeToFile’ to be doing other stuff
My (poorly chosen) example wasn’t about the side effects, but rather about the differing layers of abstraction. Almost all criticisms I’ve seen was about the “functions should be like only 4 lines” rule. Which admittetly: Is a bit whack. But no one actually pulls that rule through, do they?
I think the focus on short, simple functions combined with DRY code leads to many early, poorly chosen abstractions. Getting out from under a bad abstraction can be painful.
They do though. Loads of new people to programming read that book and create unreadable messes of a code base that follow all of his advice. I have lost count of the number of times I have inlined functions, removed layers of abstraction and generally duplicated code to get a actual understanding of what is going on only to realize there is a vastly simpler way to structure the code that I could not see until all the layers and indirection are removed. Then to refactor again to remove redundant code and apply more useful layers again that actually made sense.
And that is the problem we have with his book. People that need it take up as many bad habits as they do good ones leading to an overall decline in their code quality. It is not until years of experience that you can understand the bad bits and ignore them. So overall his book is a net negative on the programming world. Not all his advice is bad, but if you can tell that then you likely don’t need his advice.
But on the layers of abstractions specifically, he takes this too far. Largely because of the 4 line limit he has. There is a good level of abstraction and I generally find more than 2 or 3 levels of abstraction is where I start to loose any sense of what is going on. He always seems to jump on abstraction as soon as he can, but I find waiting a while and abstraction when you need to to lead to fewer and vastly better layers of abstraction overall.
And adding more abstraction does not help the people of people doing too many things inside a function - they just move it to sub functions rather than extracting the behavior for the caller to deal with. I have never seen him give advice on what that is appropriate, only keeps the functionality of the original function the same and move the logic into a nested function instead and that only covers up the issue of the function doing too much.