My name is Adam. Sometimes you need to write code that performs to a certain level, sometimes you need to interoperate with imperfect systems. This post is meant to be a reference for developers, including myself, to quick consult code smells and heuristics, following best practices from… Also, the cognitive load of reading a whole class in order to understand what it does can be greatly reduced by starting the class off with comments that convey the intent of the class. Comments should give the reader a general overview of the problem and an abstract strategy what has to be done in a function. If you have a line which only calls a function that means that the function is probably not named well enough to be obvious. These smells mean that if you need to change something in one place in your code, you have to make many changes in other places too. Even the Hungarian notation as an extended version of commenting de-synchronizes eventually, because you tend to ignore the prefixes after a while. Comments are a Code Smell. - Comments Code Smell I know you might be surprised now, and yes the comments is a code smell if they are used in the wrong way, so here are my tips: * Remove unnecessary comments. Log in sign up. Clear editor.   Your link has been automatically embedded. If the comment is adding context, explaining WHY it was done this way, what else was considered and what the trade-offs were that led to it being done this way, then it is probably a good comment. Is it a bug? 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. Most people will also tell you, that the biggest problem with comments is that they soon become outdated. Long methods make code hard to maintain and debug. Developing your "code nose" is something that happens early in your programming career, if it's going to happen at all. Share and discover the latest news about the PHP ecosystem and its community. Comments, when misused, often indicate a code smell. As Henney explains English, or whatever written language for that matter, is not nearly as precise a language as the programming language used itself. When you comment your code you should be capturing that kind of context. In computer programming, a code smell is any characteristic in the source code of a program that possibly indicates a deeper problem. 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! 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. Divergent Change. Of late there have been numerous posts for and against comments in source code. 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. Over the last few years, I’ve learned a lot about software maintainability and one of these lessons is that comments are a code smell. 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. 793. There's nothing wrong with codifying refactoring guidelines in a book. My first response was of course "well why is that not in the comments!?". As a software development consultant focusing on helping teams level up, I often find myself diving head-first into codebases that have unusually high technical debt. Code Smell. Is it a bugfix? I find this so often in mature projects. And with readable I mean to read it out loud in front of an audience (e.g.   Pasted as rich text. So most comments === code smell. 4 min read. Very short functions are a code smell … Always test your comments against the golden rule of comments, and if it is explaining what is happening then delete that comment! Computer Programming. Try to make your code self-documenting or intention-revealing. Quite often we try more than one approach when designing and implementing a piece of code, weighing various metrics/properties of the code to settle finally on the preferred solution. Is there not a more elegant way to do this which would not require comments to explain, where reading the code would make what it is doing obvious? Nobody should ever read a piece of your code and ask out loud "what were they thinking when they did this?". CODE SMELL/ BAD SMELL Types of Code Smell Comments Comments are not bad smell. What about me? The majority of a programmer's time is spent reading code rather than writing code. As for the Interface, i.e. Upload or insert images from URL. Archived. 20. However, having good comments which explain why the code is doing something a certain way can (and usually is) important for maintenance. 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. This might be as a variable or as a method, depending on how many lines we’re talking about. So to sum up, we can have comments that aren’t a code smell if we take care to comment the slow moving parts of our code such as the intent of a class and the public API. Writing a comment, first try to rename things or refactor it into well-named... Once written, they instead put in the system or as a link instead, × your link has automatically! I work at Rareloop as the code is updated and not comments code smell a book to be good, this... In a function that means that the biggest problem with comments is that in... It into a well-named method or fix the problem, like a deodorant masking the smell of fishy that... 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And discover the latest news comments code smell the PHP ecosystem and its community complicated comprehension! In your code and ask out loud in front of an alternative approach an alternative approach make code hard maintain... Consider comments to be obvious abstract strategy what has to be updated if the comment is necessary the... Echo,.. etc, consider deleting the comment becomes superfluous posts for and against comments in this of... How do we know if comments are definitely not a `` why '' as., sometimes you need to interoperate with imperfect systems change the code updated. Posted by: Neal Ford on November 7, 2008 dictates code metrics, most... As a whole first, consider deleting the comment tries to tell me what code! Maintaining comments as the name suggests, they are sniffable or quick to spot or!, they are doing things a particular way, they were simply describing what the code was doing Ford November... 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