For everything else, there’s self-documenting code and you can push all your complexity down into private methods which can be unreadable to humans and without comments as long as there are specs that express the intended behaviour. Well, I dunno. Code smells indicate a deeper problem, but as the name suggests, they are sniffable or quick to spot. … Haha, I love coders and their views on coding life. Always test your comments against the golden rule of comments, and if it is explaining what is happening then delete that comment! Is it a bugfix? Implementation should be more or less self documenting. What you were thinking should be there in plain sight, documented in the comments. You may still need to write inline comments, but this technique will help you keep them down to only when they are needed. In an object oriented language for example, the intent behind creating a class almost never changes, the public interface changes infrequently or in small increments while the implementation is frequently in flux due to refactorings and other activities. Apart from the difficulty of having to keep a lot of complex logic in mind whilst reading through a long method, it is usually a sign that the method has too many responsibilities. Consider taking the comment and using it as the name of the function instead. The term was first coined by Kent Beck while helping me with my Refactoring book. First, consider deleting the comment altogether, the code is already explaining what is being done after all. Archived. This video looks at when and how to use them to get the results you want. A code smell is a characteristic of a piece of code that does not “feel right”. The Intent of a class must be commented. If the comment tries to tell me what the code is doing, it's a "code smell". This blog has a number of great examples of how NOT to comment your code, and comical as the examples are the scary part is how often I actually see these kinds of comments in production code! Comment: Comment and document your code often as you might also not remember that a complex piece or a variable++ had solved some problems in the past. Here we have a clue as to how to write comments with a vastly reduced burden of maintainence. If you feel that a code fragment can’t be understood without comments, try to change the code structure in a way that makes comments unnecessary. This guide will help refactor poorly implemented Java if statements to make your code cleaner. Use the smell to track down the problem. The best smell is something easy to find but will lead to an interesting problem, like classes with data and no behavior. 2.9m members in the programming community. 4 min read. You should be documenting what was going on in your head when you were writing the code. But the most important guideline is to watch for warning signs in your own code – so called "code smells". When you feel like writing a comment, first try to refactor so that the comment becomes superfluous. The code is the best way to describe what the code is doing and we hope that someone trying to maintain the code is proficient in the language it is written in, so why all of the WHAT comments? If you find that you need to find the right person to maintain any piece of code in your system because "he knows what is going on in that code" or even worse "he is the only one that knows" this should be an indication that the documentation is incomplete and more often than not you will find that the comments in this code are explaining WHAT it is doing instead of the WHY's. The comments in this part of the code were of absolutely no help, they were simply describing what the code was doing. What every embedded programmer should know about ... /* don't use the global isFinite() because it returns true for null values */, Modular code and how to structure an embedded C project, #pragma config PWRTE = ON // Power-up Timer Enable bit->Power up timer disabled. Overuse or poor use of if statements is a code smell. Code Smell; Comments should not be located at the end of lines of code Code Smell; Lines should not end with trailing whitespaces Code Smell; Files should contain an empty newline at the end Code Smell; Long suffix "L" should be upper case Code Smell; Functions returns should not be invariant Analyze your code. Powered by Invision Community. On the pro-side, we have numerous posts saying comments should actually be more prominent than the code as they are an invaluable source of documentation. If you have a line which only calls a function … Just like all other code smells, comments are not universally bad, but whenever I see a comment in a piece of code my spider sense starts tingling and I immediate look a bit deeper to try and understand why comments were actually needed here. This might be as a variable or as a method, depending on how many lines we’re talking about. In such cases, comments are like a deodorant masking the smell of fishy code that could be improved. × Close. the public API, you should be documenting it with comments that feed into YARD, TomDoc or any other automatic documentation generating tools. Comments, when misused, often indicate a code smell. I would suggest the golden rule must be to test your comment by asking whether is it explaining WHY the code is done this way or if it is stating WHAT the code is doing. This is an example of self-documenting code. Share and discover the latest news about the PHP ecosystem and its community. This in turn often means that an over-commented code doesn't have a good structure or the author doesn't understand the problem well enough to abstract it. Sometimes you need to write code that performs to a certain level, sometimes you need to interoperate with imperfect systems. Mark Bernstein responded to the code smells exercise with many good observations, including: The first smell is the comment; if part of the code needs explanation, it can be explained by making it a method. Program development becomes much more complicated and expensive as a result. Comments are a Code Smell. A code smell is a hint that something has gone wrong somewhere in your code. "Comments are a code smell." Here is a list of some of the most important smells. For example if we need a comment to explain what a block of code does; try Extract method,if …   Your previous content has been restored. If you have a line which only calls a function that means that the function is probably not named well enough to be obvious. Comments == Code Smell I am sometimes asked about my position on code comments, and, like most things, I have strong opinions about it. What about me? Please … Press J to jump to the feed. As Henney explains English, or whatever written language for that matter, is not nearly as precise a language as the programming language used itself. 20. 793. Hungarian notation breaks the abstraction of having a variable name with unspecified underlying storage, so I think it is the worst way to leak implementation details!   Pasted as rich text. 793. comments anti-patterns — Fishtoaster quelle 44. Instead of documenting WHY they are doing things a particular way, they instead put in the documentation WHAT the code is doing. Bloaters are code, methods and classes that have increased to such gargantuan proportions that they are hard to work with. * Don’t leave commented old code. It is here that we want to avoid the overhead of maintaining comments as the code is free to change fast. Well, if you asked me “Are comments a code smell?” on the street the answer would probably be “Yes”, the better answer would be “It depends.” and the good answer short of this blog post would be something along the lines of: There’s a difference between documentation, which is often good, and comments. Students usually consider comments to be good, but they don't always improve things. User account menu. Encapsulating a partial solution not only brings structure to your code, it makes the function actually readable. A fundamental property of good software is that it is easy to change it, which means that it is easy to understand the code. 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