Commenting practices? - language-agnostic

As a student in computer engineering I have been pressured to type up very detailed comments for everything I do. I can see this being very useful for group projects or in the work place but when you work on your own projects do you spend as much time commenting?
As a personal project I am working on grows more and more complicated I sometimes feel as though I should be commenting more but I also feel as though it's a waste of time since I will probably be the only one working on it. Is it worth the time and cluttered code?
Thoughts?
EDIT: This has given me a lot to think about. Thanks for all your input! I never expected this large of a response.

Well considered comments illuminate when the code cannot. Well considered function and variable names eliminate the need for copious comments. If you find it necessary to comment everything, consider simplifying your code.

If you ever look at code you wrote 6 months before, you will be wondering why you did not comment better.

If the code is well written, with short methods (see Composed Method pattern) and meaningful names, then the code needs very little comments. Only comments which explain the "why" are useful - the comments explaining "what" should be replaced by improving the code so much that it's obvious what it does. Comments should not be used as an excuse for writing bad code.
Public APIs, especially in closed-source apps, are perhaps the only place where thorough javadocs are recommended - and then you need to take the effort to maintain them and keep them always accurate and up-to-date. A misleading or outdated comment is worse than no comment. It's better to document what the code does by writing tests for it and using good names for the tests.
The book Clean Code has a good chapter about comments.

Unit tests and the like are the best forms of code documentation. Some testing frameworks write out a spec of what the class under test should do, giving people a great introduction to how a piece of code works in pure english while also providing very clean way to implement the tests itself.
Examples of that are Scala's ScalaTest or RSpec for Ruby.
I find that unless some weird hacky thing is required by the code in question, it is usually not beneficial to comment it. Also, it adds a lot of overhead because you have to maintain the comments... and maintaining the code and tests is already enough work.
Remember, code with out-of-date comments is worse than no comments at all!
A lot of the time, comments just says what the code does anyway, which is a waste of human effort. And if it doesn't, your code probably sucks and you should refactor it.
Just use testing frameworks.

Comment -- or better yet, recode -- anything that is non-obvious now. Later it will be completely non-obvious. You might think, "but it's going to be me," but if your way of thinking (and ways of coding) changes as you grow what's obvious to you now might not be obvious to you later.

Have you read Code Complete yet? Recommended as a very good read, and a great way to figure out some of the things CS profs drill down your throat.
Code comments come in two variety:
Comments to explain logic, making
sure that the code matches the
intent. Often people will write high
level pseudocode and will use that
in comment form to fill in the
actual code of what the module will
do. Then they leave the comments as
a read-along which can be used
during later review.
Comments to
explain usage of a module. Think
javadocs. Your intent here is for
the consumers to understand why your
code is important. One use of
javadocs is in the Visual Studio
Intellisense (since I don't use
Eclipse idk). It shows the comments
from the javadoc in the intellisense
hover. Becomes VERY handy later on.
When professors ask you to document everything in your code, I have found the usage of psuedocode translated to actual code to be sufficient. However, in practice I've not found that many devs need it, as usually the code is sufficient to explain itself (when simple, well written, not relying on tricks, and when using descriptive variable names).
But I still put in comments about intent if I think it's the least bit unclear. This is just a bit of best practice.
But I definitely say read that book. ;)

If you ever decide to open-source your personal project, people will thank you for your comments (unless they're terrible). If you hit upon a spectacularly great idea and your personal project turns into a business, then you'll be hiring more developers, and again your comments will be valuable. If you suffer a mild head injury, then when you return to work you'll be thankful for your comments.

Some people treat comments as a code smell, a sign that the code could use more descriptive names and a better structure. They will fix the code so it does not need comments.
This works in a lot of cases. However one type of comment that is useful is 'why' something is being done. Sometimes fixes are made for obscure reasons that would not be obvious when reviewing the code later. The comments should not express what the code does (that should be covered by naming) or how it does that (again, the code tells you that), so save your comments for 'why'.
I find that nothing serves as better documentation as to how something works then unit tests.

Whenever i'm doing something that isn't self-documenting, i'll put a comment. I will forget what i was doing unless i do. But i prefer to write code that's so obvious that comments don't help much. Wherever possible, the code should be clear enough that thousands of lines of comments would be unnecessary.
Whatever you do, do NOT write comments like this...
// add 1 to i
++i;
That's noise. You're actually worse off with comments like that than with none at all.

A hard-core stance is: "if you have to write a comment for your code, your code is broken". Rather than writing explanatory comments, refactor your code so that the comments become less necessary. This applies especially to function names (including their parameters), since they tend to be modified the most, and the comments seldom are updated to match.
Instead of:
// Compute average for the two times
int a = t1 + (t2 - t1) / 2;
write
int averageTime = AverageOfTimes(t1, t2);
int AverageOfTimes(int t1, int t2) {
return t1 + (t2-t1);
}
Stale comments are one of the leading causes of WTF's when I'm reading other people's code.
Overcommenting has been cited as a "code smell" by several authors, including the authors of "Clean Code".
Personally, I write an explanatory comment for each class (I code in C# and C++ mostly), and occasionally when I am using an algorithm I want to refer to.

To be honest, if code is clear its not necessary, but comments are best when a specific logic breaks given certain data (which may not be obvious). Leaving comments of issues that may occur is a great way to help prevent accidental bugs due to misunderstandings of what data to expect (or specifically not).

I used to be in the exact same situation as you. When I first started I never commented anything because everything was extremely small and I always knew how it worked. But as I continued to expand my code and everything started pointing to each other, I found myself not knowing what certain things did anymore and got lost. I had to rewrite a lot of things so I knew what they did again, and I started commenting everything so I knew exactly how it worked and how to use it in the future. You may think you know how everything works now, but in the future you'll look back at something and say 'HUH?' It's better to comment things now and save yourself the trouble later.
The way I comment things:
Always add this at the top of any function, so you know what it does.
/**
* What the function is supposed to do, a brief description of it.
*
* #param paramter_name Object-type A description of it, do for each parameter.
*
* #return Object-type - A brief description of what is being returned.
**/
Then throughout your code make sure you comment things that look complicated. When you run checks, put a quick comment like 'make sure this is valid'. For any long lines of code or large blocks of code, add a comment of what that specific section does, to easily find it later on.

Commenting is useful for individual project as well as group projects especially when you will need to maintain or enhance the code over an extended period of time. This scenario may not be applicable for school projects, but in the workplace it is definitely applicable. If you have ever had to look at code that you wrote 6 months in the past then it might as well have been written by somebody else.

I have found that--as everyone will tell you--if you are coming back to code after several months you will have forgotten everything. That said, I hardly comment my own code except for comments like // ew.. hacked because X-beyond-my-control doesn't do Y correctly. But this is because the code itself is written very cleanly and is very easy to read. For instance, all variable and function names are completely descriptive. I don't use abbreviations except for rather long words which are obvious such as 'info'. All functions are extremely brief. All functions do one thing if possible. Nesting is avoided if possible. Logically related functions are grouped via classes or modules.
When I read other people's code, I don't read the comments. I read the code. And the difference between clear and well written code and spaghetti is far more important than any comments. Usually I don't care what their intent is/was; I want to change the code. And to do that it easily it needs to be well organized. So the comments are peripheral. But perhaps this is just me.

Technically speaking the code is perfectly self documenting. I like to comment anything that is non-obvious or especially complex. I tend to like to have at minimum summary on a class, and maybe a short blurb for each member. When you have to write a huge amount of doc on a very large and complex method that is usually a good sign that it needs to be looked at for a refactor.
foreach(var a in b.Items) //Enumerate the items in "b"
{
if(a.FirstName == "Jones") //See if first name is Jones
....
You want something in the middle of the above and no commenting whatsoever.

commenting is always useful!And I dont thik that commenting is a waste of time!It helps other developeres understand your code and it helps you when you haven't work on a project for months.

University software courses often push people towards excessive commenting as a way of forcing students to think twice about what they have typed. A nasty rule-of-thumb that was put my way when I was marking undergrad coursework a few years ago suggested a comment every 5-10 lines. Think most Java courses tell you to limit methods to circa 30 lines, so lots of comments within a function is a sign you should break it up.
My personal preference is to limit comments to documenting function purpose/inputs/outputs and data structures. Otherwise comments ought to be limited to things that require particular attention (eg things that looks out of place, perhaps bugs, at first glance).

The first comments are the variables and methods names. A lot of attention shall be paid to choose them. Do not hesitate to rename them if you can think of a better name.
Consistency and convention also help. Try to avoid NumberOfStuff, ThingCount, FooSize, always use the same form, possibly something in line with the language (does it have Array.length, or Vector.size). Always name similar things with similar names.
"Code never lies. Comments sometimes do". One day or the other, someone will modify the code and not the associated comment. Better spenf more time writing self-explanatory code complemented with some clever comment, than splitting out code and then explaining things with a lot of comments.

Rule #1
Comments should indicate WHY not 'what' (the code already tells you 'what' is happening)
Rule #2
After writing the comment - rewrite your code to read like the comment (then remove the comment)

While good variable and function names etc. may lessen the need for comments, any sufficiently complex program is going to be hard to understand merely by looking at the code alone, no matter how carefully it was written.
In general, the larger the body of code and the longer you expect it to be in use, the more important it will be to write detailed comments. It is perfectly reasonable for teachers to demand detailed comments because they don't want to have to spend a lot of time trying to understand large amounts of code from different students, but you don't necessarily have to maintain that same standard outside the classroom.
Regarding commenting functions & classes and the like, I find that only the most trivial functions are so self explanatory that a comment won't save the reader some time. Also, when you are using a smart IDE for a language such as Java or Curl writing properly formatted documentation comments will allow developers to see documentation for functions and methods simply by hovering over a call signature. This can save you a lot of time when working with large systems.

Related

How to tell someone that their mod's to my program are not good?

G'day,
This is related to my question on star developers and to this question regarding telling someone that they're writing bad code but I'm looking at a situation that is more specific.
That is, how do I tell a "star" that their changes to a program that I'd written are poorly made and inconsistently implemented without just sounding like I'm annoyed at someone "playing with my stuff"?
The new functionality added was deliberatly left out of the original version of this shell script to keep the it as simple as possible until we got an idea of the errors we were going to see with the system under load.
Basically, I'd argued that to try and second guess all error situations was impossible and in fact could leave us heading down a completely wrong path after having done a lot of work.
After seeing what needed to be added, someone dived in and made the additions but unfortunately:
the logic is not consistent
the variable names no longer describe the data they contain
there are almost no comments at all
the way in which the variables are used is not easy to follow and massively decreases readability and hence maintainability.
I always try and approach coding from the Damien Conway point of view "Always code as if your system is going to be maintained by a psychopath who knows where you live." That is, I try to make it easy for follow and not as an advertisement for my own brilliance. "What does this piece of code do?" exercises are fun and are best left to obfuscation contests IMHO.
Any suggestions greatly received.
cheers,
I would just be honest about it. You don't necessarily need to point every little detail that's wrong, but it's worth having a couple of examples of any general points you're going to make. You might want to make notes about other examples that you don't call out in the first brief feedback, in case they challenge your reasoning.
Try to make sure that the feedback is entirely about the code rather than the person. For example:
Good: The argument validation in foo() seems inconsistent with that in bar(). In foo(), a NullPointerException is thrown if the caller passes in null, whereas bar() throws IllegalArgumentException.
Bad: Your argument validation is all over the place. You throw NullPointerException in foo() but IllegalArgumentException in bar(). Please try to be consistent.
Even with a "please," the second form is talking about the developer rather than the code.
Of course in many cases you don't need to worry about being so careful, but if you think they're going to be very sensitive about it, it's worth making the effort. (Read what you've written carefully, if it's written feedback: I accidentally included a "you" in the first version to start with :)
I've found that most developers (superstar or not) are pretty reasonable about accepting, "No, I didn't implement that feature because it has problem X." It's possible that I've been lucky though.
Coming from the other perspective, I would encourage you to think about it in their shoes. I will describe a "hypothetical" experience.
Some things to keep in mind:
The guy was trying to do something
good.
Programmers are terrible at
mind reading. They tend to only know
what they read.
He may have not been given complete guidance as what needs to be done(or what doesn't need to be done)
He is likely doing the best he knows how to.
Just keep that in mind and talk to them. Teach them. No need for yelling or pissing contests. Just remember that they are not intentionally trying to make your life difficult.
I see that you've asked a lot of questions about how to deal with certain kinds of developers. It seems to be a common thread for you. You keep asking about how to change people around you. If this is a constant problem for you, then perhaps you are the problem.
Now I know you are asking questions to learn how to deal with people you find difficult, and that's good, however, you keep asking (and getting answers) about how to change people.
It seems to me that you need to change. Work with these people to change the code to what you want it to be. With them. Don't try to get them to do it. Just do it, and tell them what you did and why, and ask suggestions for further improvement, and learn from each other. Play off of each other's experience and strengths. Just my 2 cents.
If you have clearly defined coding standards for the project, point out that the code needs to be changed to meet those standards. The list you have there seems like quite reasonable feedback (though #3 is much argued-over; I would only push to document the really confusing parts as fixing the other three points, hopefully, makes the code less confusing).
If there are any other examples you have in your repository from this developer that are several months old, show one to him and ask him what it is doing. (Show him this one in a few months). When he has to zip around to find out what is actually in his variables, and deconstructing every line of code to figure out what it is doing. Break into a code review / pair programming session right there. Refactor and rename together so that he hopefully begins to see for himself exactly why these things are important.
Frankly, I think this is a political problem, not a coding problem. Specifically...
WHO SAID THIS PERSON WAS A "STAR"? If this is the same person you described in your other question, then you already have your answer there: THIS PERSON IS NO "STAR".
So then you get into the other effects of politics...
Who is claiming this person to be a star? Why can you not just tell the person "this is crap code"? Who is protecting them / defending them were you to do that? Can you do that or would you get blasted / demoted / put on the "to be laid off" pile?
You are asking questions that cannot really be answered in isolation. IF the code is crap, then throw it away and do it correctly yourself. IF there are reasons that you cannot do that, then you need to ask yourself if the benefits of this place outweigh the negatives.
Cheers,
-R
Creating a program and then releasing it to be worked on by other developers is tough. You are throwing your code to the mercy of others' development styles, coding conventions, etc.
Telling those developers that they are doing coding poorly, after the code is in, is one of the hardest things that you can do. It is best to address your concerns before they ever start working with your code. This can be done in two ways: Maintaining a detailed coding standard, requiring that submitted code adheres to this and maintaining a development road map, not to just outline when new features will be in, but to create dependencies to avoid such mishaps.
More to your situation, it is important not to criticize or it could cause hostility and worse code coming in. Maybe you can work with that developer to create standards documentation. You will be able to express your ideas about what the standards should be, and you will get their input, without causing any hard feelings.
Always point out the good things in their code, and be sure when discussing the weaknesses that you frame them pointing out the reasons that it will benefit everyone (the developer included), never criticize.
Good luck.
I would do the following:
Make sure he knows that his hard work is appreciated (preferably, this should be the truth)
Ask him if he would mind making a few changes, making it sound like no big deal and easy to fix
Explain the issues, including why they are issues, and suggest specific changes to set him on the right path.
Hopefully, the exercise will help him integrate into the culture project better.
We try to solve these potential 'issues' proactively:
Every 'bigger' project where people work together gets assigned a project 'codelead' (one of the developers). This rotates every project (based on preferences, experience with the particular task ...) so everyone gets to be in the 'contributing' and 'code-project-lead' roles once in a while.
We explicitely made an agreement that
these project 'leads' can decide
whatever they want to with the code
contributions of the others (sort of
like a temporary dictatorship: change
it, make suggestions, ask people to
redo stuff etc.). The projectcode
'lead' bears the complete
responsibility for the aggregated
code to work.
With these formalised 'leads' (and the changing roles) I think people have less problems with (constructive) criticism of the parts they contribute.
Yes, keep the feedback as appreciative, professional and technical as possible, back up your concerns with possible "worst case" scenarios so that the disadvantages of those features and/or this particular implementation, become blatantly obvious.
Also, if this is about features/code that are very specific and are not of any use to most users, express your concerns about the code/use ratio - indicating concerns about increased code base complexity etc.
Ideally, present your concerns as open-ended questions - in the sense of: "Though, I am wondering if this way of doing it may work in the long term, due to ...". So that you actually encourage an active dialogue between contributors.
Invite your fellow contributors and user to provide their opinions on these concerns, in fact ask other people/contributors what they are thinking about this addition (in terms of pros & cons, requirements, code quality), do make the statement that you are willing to reconsider your current position if other contributors/users can provide corresponding insight.
You are basically encouraging an informal review that way, asking your community to also look into the proposed additions, so that the advantages and disadvantages can be discussed.
So, whatever the decision will be, it will be one that is community-backed, and not just simply made by you.
You being the architect of the original design, are also in an excellent position to provide architectural reasons why something is not (yet) suitable for inclusion/deployment.
If stability, complexity or code quality are a real concern, do illustrate how other contributions also had to go through a certain review process in order to be acceptable.
You can also mention how specific code doesn't really align with your current design, or how it may not scale too well with future extension to your current design, similarly you can highlight why certain stuff was left out explicitly.
If you actually like the features or the core idea, be sure to highlight the excellent addition these features would make if properly implemented and integrated, but do also highlight that the existing implementation isn't really appropriate due to a number of reasons.
If you can, do make specific suggestions for improvements, provide examples of how to do things better, and what to avoid and do express that you hope, this can be reworked to be added with the help of your project's community.
Ideally, present your requirements for actually accepting this contribution and do mention the background for your requirements, you may in fact say that you hate some of these requirements yourself.
Preferably, present and discuss instances where you yourself contributed similar code (or even worse code) and that you ended up facing huge issues due to your own code, so that these policies are now in place to prevent such issues. By actually talking about your own bad code, you can actually be very subjective.
Emphasize that you generally appreciate the effort itself, and that you are willing to provide the necessary help and pointers to bring the code in question into a better shape and form. Also, encourage that similar contributions in the future should be properly coordinated within your community, in order to avoid similar issues.
Always think in terms of features and functionality (and remind your contributor to do the same), not code - imagine it like a thorough code review process, where the final code that ends up being committed/accepted, may have hardly anything in common with the original implementation.
This is again a good possibility, to present examples where you yourself developed code that ended up largely reworked, so that much of it is now replaced by a much better implementation.
Similarly, there's always the issue with code that has no active maintainers, so you can just as easily suggest that you feel concerned about code that may end up being unmaintained, you could even ask if the corresponding developer would be willing to help maintain that code, possibly in a separate branch.
In the same sense, always require new code to be accompanied with proper comments, documentation and other updates. In other words, code that adds new or changes existing functionality, should always be accompanied with updates to all relevant documentation.
Ultimately, if you know right away that you cannot and will not accept any of that code in the near future, you can at least invite the developer to branch or even fork your project, possibly in you repository and with your help and guidance, so that you still express your gratitude for working with your project.

How to convince your fellow developer to write short methods?

Long methods are evil on several grounds:
They're hard to understand
They're hard to change
They're hard to reuse
They're hard to test
They have low cohesion
They may have high coupling
They tend to be overly complex
How to convince your fellow developer to write short methods? (weapons are forbidden =)
question from agiledeveloper
Ask them to write unit tests for the methods.
That depends on your definitions of "short" and "long".
When I hear someone say "write short methods", I immediately react badly because I've encountered too much spaghetti written by people who think the ideal method is two lines long: One line to do the tiniest possible unit of work followed by one line to call another method. (You say long methods are evil because "they're hard to understand"? Try walking into a project where every trivial action generates a call stack 50 methods deep and trying to figure out which of those 50 layers is the one you need to change...)
On the other hand, if, by "short", you mean "self-contained and limited to a single conceptual function", then I'm all for it. But remember that this can't be measured simply by lines of code.
And, as tydok pointed out, you catch more flies with honey than vinegar. Try telling them why your way is good instead of why their way is bad. If you can do this without making any overt comparisons or references to them or their practices (unless they specifically ask how your ideas would relate to something they're doing), it'll work even better.
You made a list of drawbacks. Try to make a list of what you'll gain by using short methods. Concrete examples. Then try to convince him again.
I read this quote from somewhere:
Write your code as if the person who has to maintain it is a violent psycho, who knows where you live.
In my experience the best way to convince a peer in these cases is by example. Just find opportunities to show them your code and discuss with them the benefits of short functions vs. long functions. Eventually they'll realize what's better spontaneously, without the need to make them feel "bad" programmers.
Code Reviews!
I suggest you try and get some code reviews going. This way you could have a little workshop on best practices and whatever formatting your company adhers to. This adds the context that short methods is a way to make code more readable and easier to understand and also compliant with the SRP.
If you've tried to explain good design and people just aren't getting it, or are just refusing to get it, then stop trying. It's not worth the effort. All you'll get is a bad rep for yourself. Some people are just hopeless.
Basically what it comes down to is that some programmers just aren't cut out for development. They can understand code that's already written, but they can't create it on their own.
These folks should be steered toward a support role, but they shouldn't be allowed to work on anything new. Support is a good place to see lots of different code, so maybe after a few years they'll come to see the benefits of good design.
I do like the idea of Code Reviews that someone else suggested. These sloppy programmers should not only have their own code reviewed, they should sit in on reviews of good code as well. That will give them a chance to see what good code is. Possibly they've just never seen good code.
To expand upon rvanider's answer, performing the cyclomatic complexity analysis on the code did wonders to get attention to the large method issue; getting people to change was still in the works when I left (too much momentum towards big methods).
The tipping point was when we started linking the cyclomatic complexity to the bug database. A CC of over 20 that wasn't a factory was guaranteed to have several entries in the bug database and oftentimes those bugs had a "bloodline" (fix to Bug A caused Bug B; fix to Bug B caused Bug C; etc). We actually had three CC's over 100 (max of 275) and those methods accounted for 40% of the cases in our bug database -- "you know, maybe that 5000 line function isn't such a good idea..."
It was more evident in the project I led when I started there. The goal was to keep CC as low as possible (97% were under 10) and the end result was a product that I basically stopped supporting because the 20 bugs I had weren't worth fixing.
Bug-free software isn't going to happen because of short methods (and this may be an argument you'll have to address) but the bug fixes are very quick and are often free of side-effects when you are working with short, concise methods.
Though writing unit tests would probably cure them of long methods, your company probably doesn't use unit tests. Rhetoric only goes so far and rarely works on developers who are stuck in their ways; show them numbers about how those methods are creating more work and buggy software.
Finding the right blend between function length and simplicity can be complex. Try to apply a metric such as Cyclomatic Complexity to demonstrate the difficulty in maintaining the code in its present form. Nothing beats a non-personal measurement that is based on testing factors such as branch and decision counts.
Not sure where this great quote comes from, but:
"Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it"
Force him to read Code Complete by Steve McConnell. Say that every good developer has to read this.
Get him drunk? :-)
The serious point to this answer is the question, "why do I consistently write short functions, and hate myself when I don't?"
The reason is that I have difficulty understanding complex code, be that long functions, things that maintain and manipulate a lot of state, or that sort of thing. I noticed many years ago that there are a fair number of people out there that are significantly better at dealing with this sort of complexity than I am. Ironically enough, it's probably because of that that I tend to be a better programmer than many of them: my own limitations force me to confront and clean up that sort of code.
I'm sorry I can't really provide a real answer here, but perhaps this can provide some insight to help lead us to an answer.
Force them to read the book "Clean Code", there are many others but this one is new, good and an easy read.
Asking them to write Unit tests for the complex code is a good avenue to take. This person needs to see for himself what that debt that complexity brings when performing maintenance or analysis.
The question I always ask my team is: "It's 11 pm and you have to read this code - can you? Do you understand under pressure? Can you, over the phone, no remote login, lead them to the section where they can fix an error?" If the answer is no, the follow up is "Can you isolate some of the complexity?"
If you get an argument in return, it's a lost cause. Throw something then.
I would give them 100 lines of code all under 1 method and then another 100 lines of code divided up between several methods and ask them to write down an explanation of what each does.
Time how long it takes to write both paragraphs and then show them the result.
...Make sure to pick code that will take twice or three times as long to understand if it were all under one method - Main() -
Nothing is better than learning by example.
short or long are terms that can be interpreted differently. For one short is a 2 line method while some else will think that method with no more than 100 lines of code are pretty short.
I think it would be better to state that a single method should not do more than one thing at the same time, meaning it should only have one responsibility.
Maybe you could let your fellow developers read something about how to practice the SOLID principles.
I'd normally show them older projects which have well written methods. I would then step through these methods while explaining the reasons behind why we developed them that way.
Hopefully when looking at the bigger picture, they would understand the reasons behind this.
ps. Also, this exercise could be used in conjuction as a mini knowledge transfer on older projects.
Show him how much easier it is to test short methods. Prove that writing short methods will make it easier and faster for him to write the tests for his methods (he is testing these methods, right?)
Bring it up when you are reviewing his code. "This method is rather long, complicated, and seems to be doing four distinct things. Extract method here, here, and here."
Long methods usually mean that the object model is flawed, i.e. one class has too many responsibilities. Chances are that you don't want just more functions, each one shorter, in the same class, but those responsibilies properly assigned to different classes.
No use teaching a pig to sing. It wastes your time and annoys the pig.
Just outshine someone.
When it comes time to fix a bug in the 5000 line routine, then you'll have a ten-line routine and a 4990-line routine. Do this slowly, and nobody notices a sudden change except that things start working better and slowly the big ball of mud evaporates.
You might want to tell them that he might have a really good memory, but you don't. Some people are able to handle much longer methods than others. If you both have to be able to maintain the code, it can only be done if the methods are smaller.
Only do this if he doesn't have a superiority complex
[edit]
why is this collecting negative scores?
You could start refactoring every single method they wrote into multiple methods, even when they're currently working on them. Assign extra time to your schedule for "refactoring other's methods to make the code maintanable". Do it like you think it should be done, and - here comes the educational part - when they complain, tell them you wouldn't have to refactor the methods if they would have made it right the first time. This way, your boss learns that you have to correct other's lazyness, and your co-workers learn that they should make it different.
That's at least some theory.

Should code be short/concise? [closed]

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When writing a mathematical proof, one goal is to continue compressing the proof. The proof gets more elegant but not necessarily more readable. Compression translates to better understanding, as you weed out unnecessary characters and verbosity.
I often hear developers say you should make your code foot print as small as possible. This can very quickly yield unreadable code. In mathematics, it isn't such an issue since the exercise is purely academic. However, in production code where time is money, having people try to figure out what some very concise code is doing doesn't seem to make much sense. For a little more verbose code, you get readability and savings.
At what point do you stop compressing software code?
I try to reach a level of verbosity where my program statements read like a sentence any programmer could understand. This does mean heavily refactoring my code such that it's all short pieces of a story, so each action would be described in a separate method (an even further level might be to another class).
Meaning I would not reduce my number of characters just because it can be expressed in fewer. That's what code-golf competitions are for.
My rule is say what you mean. One common way I see people go wrong is "strength reduction." Basically, they replace the concept they are thinking with something that seems to skip steps. Unfortunately, they are leaving concepts out of their code, making it harder to read.
For example, changing
for (int i = 0; i < n; i++)
foo[i] = ...
to
int * p = foo, q = foo+n;
while ( *p++ = ... < q );
is an example of a strength reduction that seems to save steps, but it leaves out the fact that foo is an array, making it harder to read.
Another common one is using bool instead of an enum.
enum {
MouseDown,
MouseUp
};
Having this be
bool IsMouseDown;
leaves out the fact that this is a state machine, making the code harder to maintain.
So my rule of thumb would be, in your implementation, don't dig down to a lower level than the concepts you are trying to express.
You can make code smaller by seeing redundancy and eliminating it, or by being clever. Do the former and not the latter.
Here's a good article by Steve McConnell - Best Practices http://www.stevemcconnell.com/ieeesoftware/bp06.htm
I think short/concise are two results from well written code. There are many aspects to make code good and many results from well written code, realize the two are different. You don't plan for a small foot print, you plan for a function that is concise and does a single thing extremely well - this SHOULD lead to a small foot print (but may not). Here's a short list of what I would focus on when writing code:
single focused functions - a function should do only one thing, a simple delivery, multi featured functions are buggy and not easily reusable
loosely coupled - don't reach out from inside one function to global data and don't rely heavily on other functions
precise naming - use meaningful precise variable names, cryptic names are just that
keep the code simple and not complex - don't over use language specific technical wow's, good for impressing others, difficult to easily understand and maintain - if you do add something 'special' comment it so at least people can appreciate it prior to cursing you out
evenly comment - to many comments will be ignored and outdated to few have no meaning
formatting - take pride in how the code looks, properly indented code helps
work with the mind of a code maintenance person - think what it would be like to maintain the code you're writting
do be afraid or to lazy to refactor - nothing is perfect the first time, clean up your own mess
One way to find a balance is to seek for readability and not concise-ness. Programmers are constantly scanning code visually to see what is being done, and so the code should as much as possible flow nicely.
If the programmer is scanning code and hits a section that is hard to understand, or takes some effort to visually parse and understand, it is a bad thing. Using common well understood constructs is important, stay away from the vague and infrequently used unless necessary.
Humans are not compilers. Compilers can eat the stuff and keep moving on. Obscure code is not mentally consumed by humans as quickly as clearly understood code.
At times it is very hard to produce readable code in a complicated algorithm, but for the most part, human readability is what we should look for, and not cleverness. I don't think length of code is really a measure of clearness either, because sometimes a more verbose method is more readable than a concise method, and sometimes a concise method is more readable than a long one.
Also, comments should only supplement, and should not describe your code, your code should describe itself. If you have to comment a line because it isn't obvious what is done, that is bad. It takes longer for most experienced programmers to read an English explanation than it does to read the code itself. I think the book Code Complete hammers this one home.
As far as object names go, the thinking on this has gone through an evolution with the introduction of new programming languages.
If you take the "curly brace" languages, starting with C, brevity was considered the soul of wit. So, you would have a variable to hold a loan value named "lv", for instance. The idea was that you were typing a lot of code, so keep the keystrokes to a minimum.
Then along came the Microsoft-sanctioned "Hungarian notation", where the first letters of a variable name were meant to indicate its underlying type. One might use "fLV", or some such, to indicate that the loan value was represented by a float variable.
With Java, and then C#, the paradigm has become one of clarity. A good name for a loan value variable would be "loanValue". I believe part of the reason for this is the command-completion feature in most modern editors. Since its not necessary to type an entire name anymore, you might as well use as many characters as is needed to be descriptive.
This is a good trend. Code needs to be intelligible. Comments are often added as an afterthought, if at all. They are also not updated as code is updated, so they become out of date. Descriptive, well-chosen, variable names are the first, best and easiest way to let others know what you were coding about.
I had a computer science professor who said "As engineers, we are constantly creating types of things that never existed before. The names that we give them will stick, so we should be careful to name things meaningfully."
There needs to be a balance between short sweet source code and performance. If it is nice source and runs the fastest, then good, but for the sake of nice source it runs like a dog, then bad.
Strive to refactor until the code itself reads well. You'll discover your own mistakes in the process, the code will be easier to grok for the "next guy", and you won't be burdened by maintaining (and later forgetting to change) in comments what you're already expressed in code.
When that fails... sure, leave me a comment.
And don't tell me "what" in the comment (that's what the code is for), tell me "why".
As opposed to long/rambling? Sure!
But it gets to the point where it's so short and so concise that it's hard to understand, then you've gone too far.
Yes. Always.
DRY: Don't Repeat Yourself. That will give you a code that is both concise and secure. Writing the same code several times is a good way to make it hard to maintain.
Now that does not mean you should make a function of any blocks of code looking remotely alike.
A very common error (horror ?) for instance is factorizing code doing nearly the same thing, and to handle the differences between occurences by adding a flag to function API. This may look inocuous at first, but generates code flow hard to understand and bug prone, and even harder to refactor.
If you follow common refactoring rules (looking about code smells) your code will become more and more concise as a side effect as many code smells are about detecting redundancy.
On the other hand, if you try to make the code as short as possible not following any meaningfull guidelines, at some point you will have to stop because you just won't see any more how to reduce code.
Just imagine if the first step is removing all useless whitespaces... after that step code in most programming languages will become so hard to read you won't have much chance to find any other possible enhancement.
The example above is quite caricatural, but not so far from what you get when trying to optimise for size without following any sensible guideline.
There's no exact line that can be drawn to distinguish between code that is glib and code that is flowery. Use your best judgment. Have others look at your code and see how easily they can understand it. But remember, correctness is the number 1 goal.
The need for small code footprints is a throwback from the days of assembly language and the first slightly high level languages... there small code footprints where a real and pressing need. These days though, its not so much of a necessity.
That said, I hate verbose code. Where I work, we write code that reads as much as possible like a natural language, without any extra grammar or words. And we don't abbreviate anything unless its a very common abbreviation.
Company.get_by_name("ABC")
makeHeaderTable()
is about as terse as we go.
In general, I make things obvious and easy to work with. If concision/shortness serves me in that end, all the better. Often short answers are the clearest, so shortness is a byproduct of obvious.
There are a couple points to my mind that determine when to stop optimizing:
Worth of spending time performing optimizations. If you have people spending weeks and not finding anything, are there better uses of those resources?
What is the order of optimization priority. There are a few different factors that one could care about when it comes to code: Execution time, execution space(both running and just the compiled code), scalability, stability, how many features are implemented, etc. Part of this is the trade off of time and space, but it can also be where does some code go, e.g. can middleware execute ad hoc SQL commands or should those be routed through stored procedures to improve performance?
I think the main point is that there is a moderation that most good solutions will have.
The code optimizations have little to do with the coding style. The fact that the file contains x spaces or new lines less than at the beginning does not make it better or faster, at least at the execution stage - you format the code with white characters that are unsually ignored by the compiler. It even makes the code worse, because it becomes unreadable for the other programmers and yourself.
It is much more important for the code to be short and clean in its logical structure, such as testing conditions, control flow, assumptions, error handling or the overall programming interface. Of course, I would also include here smart and useful comments + the documentation.
There is not necessarily a correlation between concise code and performance. This is a myth. In mature languages like C/C++ the compilers are capable of optimizing the code very effectively. There is cause need in such languages to assume that the more concise code is the better performing code. Newer, less performance-optimized languages like Ruby lack the compiler optimization features of C/C++ compilers, but there is still little reason to believe that concise code is better performing. The reality is that we never know how well code will perform in production until it gets into production and is profiled. Simple, innocuous, functions can be huge performance bottlenecks if called from enough locations within the code. In highly concurrent systems the biggest bottlenecks are generally caused by poor concurrency algorithms or excessive locking. These issues are rarely solved by writing "concise" code.
The bottom line is this: Code that performs poorly can always be refactored once profiling determines it is the bottleneck. Code can only be effectively refactored if it is easy to understand. Code that is written to be "concise" or "clever" is often more difficult to refactor and maintain.
Write your code for human readability then refactor for performance when necessary.
My two cents...
Code should be short, concrete, and concentrated. You can always explain your ideas with many words in the comments.
You can make your code as short or compact as you like as long as you comment it. This way your code can be optimized but still make sence. I tend to stay in the middle somewhere with descriptive variables and methods and sparce comments if it is still unclear.

Referencing other peoples code

I'm currently working on my Bachelors dissertation. This involves developing a software product and a 12000 word write-up, mainly covering research, design and development. Now where I am quoting other peoples written work, I am obviously referencing this, but what about code? There have been plenty of times where I've looked for a solution to a problem I was unsure of and found someone who had solved the problem. Most of the time I took their code, worked to understand what they were doing, and then wrote my own version in my application, so should it be referenced somehow?
What would you guys do, put a comment in the code referencing the original author, add a reference in the write up or my bibliography, or nothing at all?
Where its a significant or interesting piece of code used, I will probably refer to it in my write-up, but for solutions that don't warrant this, I’m trying to come up with a good solution.
If you were the author of some code I had either used, or been inspired by, what would make you happy that I wasn't plagiarizing you?
To take this a bit further, there's really 2 different things here. If I go to MSDN to lookup how to use a particular part of the .net framework, is that something that should be referenced, or is it fair use of the framework.
Where as if I've used an algorithm that someone clearly developed and put a lot of time into, that's something I would definitely reference.
It all depends on context. Many algorithms are so well known that they are generally considered public domain and as long as you reference a well known source on the subject then you shouldn't have any worries (Sorting, Searching)
When dealing with specific problems, especially in other people code, you have to read really carefully. If its published (book, journal, web, etc..) then you must always reference the original, at some point in your dissertation (technically once in then write up and then a comment in the source)
If it's other peoples work they deserve proper credit. Anything else is plagiarism
There's two aspects to this:
The citation requirements of your academic institution. You should make sure you comply with this because if you're found to have plagiarised another's work you can be guilty of academic misconduct and you don't want that; and
The ethics of using another's work. Barring "fair use" provisions (meaning there's only so much of someone's work you can reproduce before what you're doing is no longer "fair use") and the like, if you reproduce someone else's code, that you should credit. If you simply take the idea, that's possibly a bit different and is a judgement call. It depends on the significance of that idea and it's contribution to your work.
Outside of academic work, I make it a habit to leave a comment in my source code if I reference someone else to solve a particular problem. It's for my benefit as well, I might want to go back and take another look at their code months later and have forgotten where I originally found it. Of course, take a look at the included license when you reference someone's code, it should be pretty clear what you can't do with it.
There's no shame in borrowing working code if it's the best tool for the job, provided the author's licence conditions allow it - real programmers do it all the time. But for academic purposes there is a problem if you could be percieved as being at all secretive or deceptive about it. To avoid that, I'd reference it both in the code with a big, clear comment, and in the report. Full disclosure means you can't be accused of doing anything wrong.
I have the same issue for my dissertation as well:
I opt for referencing without overdoing it. Adding a reference to the referenced section, means that you've searched, found something, thought of using it and accepted it, while having nothing means that you made it up. This increases the value of your work in academical context (the more you base on previous work, the better).
Also your supervisor will be able to trace license and algorithmic issues on the referenced site.
At last you do not know where your work will get to. Suppose in 3 years after today someone tries to use it, and jumps into a patent violation? How can you help him - by a reference...

Are comments necessary for a programming language? [closed]

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After some stupid musings about Klingon languages, that came from this post I began a silly hobby project creating a Klingon programming language that compiles to Lua byte-code. During the initial language design phase I looked up information about Klingon programmers, and found out about this Klingon programming rule:
A TRUE Klingon Warrior does not comment his code!
So I decided my language would not support commenting, as any good Klingon would never use them.
Now many of the Klingon ways don't seem reasonable to us Human programmers, however while dabbling with the design and implementation of my hobby language I came to realize that this Klingon rule about commenting is indeed very reasonable, if not great.
Removing the ability to comment from a programming language meant I HAVE to write literate code, no exceptions.
So it got me wondering if there are any languages out there that don't support comments?
Is there are any really good arguments to not remove commenting from a language?
Edit: Any good examples of comments required?
P.S.> My hobby language above is partially silly anyways, so don't focus too much on my implementation, as much as the concept of comments required in general
Do not comment WHAT you are doing, but WHY you are doing it.
The WHAT is taken care of by clean, readable and simple code with proper choice of variable names to support it. Comments show a higher level structure to the code that can't be (or is hard to) show by the code itself.
I am not sure I agree with the "Have" in the statement "Removing the ability to comment from a programming language meant I HAVE to write literate code, no exceptions", since it is not as if all code is documented. My guess is that most people would write unreadable code.
More to the point, I personally do not believe in the reality of the self-explanatory program or API in the practical world.
My experience from manually analyzing the documentation of entire APIs for my dissertation suggests that all too often you would have to carry more information than you could convey in the signature alone. If you eliminate interface comments from your language, what are the alternatives? No documentation is not an option. External documentation is less likely to be read.
As for internal documentation, I can see your point in wanting to reduce documentation to convince people to write better. However, comments serve many collaboration and coordination purposes and are meant to raise awareness of things. By banishing these details to extenral locations, you are reducing the chances that they come to a future reader's awareness, unless your tooling is great.
Ugh, not being able to quickly comment out a line (or lines) during testing sounds annoying to me, especially when scripting.
In general comments are a wart that indicates poor design, especially long rambling comments where its clear the developer didn't have a clue what the heck they where doing and tried to make up for it by writing a comment.
Places where comments are useful:
Leaving a ticket number next to a fix so future programmers can understand business requirements
Explaining a particularly tricky hack
Commentary on business logic for a piece of code
Terse descriptions in API docs so a third-party can use your API
In all circumstances programmers should endeavor to write code that is descriptive and NOT write comments that describe poorly written code. That being said I think there are plenty of valid reasons that languages should and must support comments.
Your code has two distinct audiences:
The compiler
Human beings like us
If you choose to remove comments altogether, the assumption you are taking is that you will be catering only to the compiler, and to nothing else.
Of course you, being Klingon, may not need comments because you are not human. Perhaps you could clearly demonstrate to us your ability by speaking in IL instead?
You don't need a single assertion in your code because, in release mode, they're all gone. But when C++ didn't have assertions built-in, someone wrote the assert macro to replace it.
Of course you don't need comments, either, for more or less the same reason. But if you design a language without comments, people will start doing things like:
HelperFunctionDoesNothing("This is a comment! Blah Blah Blah...");
I'm curious. How do you stop someone from declaring a static string containing a comment and then ignoring the variable for the rest of the func/method/procedure/battle/whatever?
var useless_comment = "Can we destroy our enemies?"
if (phasers on full) return Qapla'
Languages need comments. At least 95% of comments can be replaced by clearer code but there are still assumptions you need to document and you absolutely need to document if there's some external problem you are working around.
I never write a comment without first considering if I can change the code to eliminate the need for it but sometimes you can't.
While all source code is copyrighted by default. It is often nice to:
remind the person reading the source code that it is subject to copyright
tell people what the licensing terms are for that source code file
tell them whether or not they are looking at a protected trade secret
Unfortunately, without comments, it is difficult to do this.
Am I the only one who comments out a couple of lines code for a number of purposes?
It's going to be harder than you think to make a language where comments are impossible.
if (false) {
print("This is a comment. Chew on that, Klingons!")
}
While it's true that humans need to be able to comment code, it is not absolutely necessary that the language directly support commenting: for most languages, it would be trivial to write a script that deletes one line comments (for example, all lines beginning with '#' or some other character) then runs the compiler.
Actually, though, I am surprised and disappointed to learn that even my favorite esoteric programming languages support comments: Brainf**k and Whitespace. These languages are meant to be hard to read, so it seems like they shouldn't support commenting. (As opposed to my other favorite esoteric language: LOLCode, which is meant to be self-documenting, in lolcats-speech)
I would dissent from the other answerers on this point: I say, be true to your vision of a Klingon programming language, and do not support comments!
A point against comments is that they tend to often fall out of date with the code. Any time you add a redundancy, you're risking this sort of inconsistency.
There's actually some interesting research that I've seen when a group used NLP to analyze locking comments in some large system and then compare them to the results of static analysis and were able to fix a few bugs that way.
Isn't literate programming as much comment as it is code? Certainly, much of what I've seen of literate programming has as much explanation as code, if not more comment.
You might think that developers writing in your language will make an extra effort to write clear code but the onus will actually be on you to design a language that's so expressive that it doesn't need to be commented. Hell, not even English is like that (we still parenthesize!). If your language isn't so designed it may very well be as usable as Brainfuck and enjoy the popularity and respect of Brainfuck.
Should I add links or are links considered commentlike?
Besides, people will find ways to add comments if they need to by highjacking strings and misusing variable names (that do nothing other than stand in for comments). Have you read Godel Escher Bach?
It will be a bad idea to remove the commenting facility altogether. Surely developers must learn to write code with minimum comments i.e. to write self documenting code but there a lot of cases where one has to explain why something is being done the way it is. Consider the following cases:
a new developer might start maintaining the code and the original dev has left/ out of the project
a change in specification or market requirement leads to something that is counter intuitive
copy right notice especially if open source (some open source libs require you to do this)
It is also my experience that new programmers tend to comment more and as they develop expertise their code tends to become self documenting and concise. In general comments should be about WHY and not HOW or WHAT.
NO -- there is not a single programming language out there that requires comments.
The language is for the computer. The comments are for the humans. You can write a program with 0% comments. It'll execute, rightly or wrongly. You can't write a program with 100% comments. It'll either not compile -- no main(), etc. -- or, for scripting languages, do exactly nothing.
And, besides, real programmers don't comment their code. Just like Klingons.
While I agree with Uri's responses, I too have made a language with no comments. (ichbins.) The language was to be as simple as possible while still being able to express its own compiler cleanly; since you can do that without comments, they got jettisoned.
I'm working off and on on a revision that does support commentary, but a bit differently: literate-programming style with code nested in text instead of comments embedded in code. It might also get examples/test-cases later as a first-class language feature.
Good luck with the Klingon hacking. :-)
I can't tell you how thankful I am for Javadoc - which is really simple to set up within comments. So that's at least one sense in which comments are useful.
No, of course a language doesn't have to have commenting. But a (useful) program does have to have comments... I don't agree with your idea that literate code lacks comments. Some very good code is easily comprehensible with comments, but only with difficulty without.
I think the comments are required in many situations.
For instance, think of the algorithmic ones. Suppose there is a function written in C which solves the Traveling Salesperson Problem, there are wide range of techniques that can be used to deal with this problem. And the codes are usually cryptic by its nature.
Without explicitly describing the parameters and the algorithm used, by using comments, it is almost impossible to reuse this piece of code.
Can we live without comments on code? Sure, but that won't make live easier.
Comments are useful because they reassure the person reading your code - probably the "future you" - that you've thought about her welfare.
I think the question may become how self-contained would the language without comments be? If for example, it compiles down to DLLs that get used within other code, then how does one know anything beyond the function signature in terms of what it requires, changes and returns? I wouldn't want to have function names being dozens of characters to try to express what may be very easily done with comments above the function that can be used as documentation within something like the Object Browser within Visual Studio for example.
Of course!!
The main reason is novice developers. Not everyone knows how to write literate code. Actually there are millions out there don't get a NullPointerException when they see one.
We all start at some point.
But if you're targeting to "expert" developers only, why bother in the language in first place. You should be using butterflies !!! That's what real developer use!
Comments is a must, try to make it harder if you wish ( like using #//##/ sequence to create a comment or something like that ) but don't leave it out.
:)
I agree with you that nicely written code does not need any comments as "Code is only good documentation available to programmer. However this is very ideal condition, not everyone writes good code all time.
So to make poorly written code good in future comments are required.
I once wrote a VB app (a silly board game inspired by Monopoly) without any comments. But I did that just to piss off my teacher, who had told us comments were for "whatever we found relevant, so we could remember it later".
Perfect code needs zero comments. It should be simple, and understandible by complete novices.
Any code needs comments, I try to explain the reason for and workings of every function I write in 1 or 2 lines.
Code that explains itself only exists in a perfect world, there is always some weird hack or a reason to do something quick-n-dirty instead of the propper way.
The best thing to remember is to comment WHY code does what it does, good code explains WHAT it does 99% of the time.
Write something simple, like a piece of code that can solve a Sudoku puzzle (3 reasonably simple while loops) and try reading that 3 months later. You will immidiatly find something that isn't exactly clear.
Code is written once, but read many times over the course of its lifetime; thus it pays to optimize for readability. Clear and consistent naming of everything from constants to classes is necessary, but may or may not be sufficient to achieve this objective. If not, fill in the gaps with comments, and maintain them as you would the code.