Related
My initial take on XCode is that it makes hard things easier, and easy things harder (find & replace requires way too many keystrokes, for example...). The biggest one to me, however is a lack of a method wizard... I tend to write lots of small methods, and I'm finding it hard to believe that you can't declare your method in a popup and have the interface and implementation files populated with stubs. Am I missing something? Frankly, I get far more functionality out of vi from an editor perspective.
I don't think you can do that exactly as you want it (without a plugin like Accessorizer), but it's not necessary, since you can create your own snippets, as highlighted in this snippet question, that will then contain the stubs you really need. Since most basic methods are written for you (or only require a few keywords to be autogenerated with your requirements, with #synthesize, etc...), it makes sense to me.
However, this could make your day if you still are unhappy :D
I see that some programmers add code that, after all, does not do anything useful. For instance (C#):
[Serializable]
class Foo {
// ...
string SerializeMe() {
return new XmlSerializer(typeof(this)).Serialize(this).ToString(); // serialize to xml (syntax wrong, not important here)
}
}
The class is marked as Serializable, but the only way it is serialized is by means of XmlSerialization, which does not require that class attribute at all.
I personally hate this kind of useless code, but I see it quite often and I'm curious as to what others think about it. Is this not so serious a flaw after all? Is it common practice in the industry? Or is this just plain bad and should be removed no matter what?
Good Source Control means that useless code or code that is no longer required should be removed. It can always be retrieved from the source control at a later date.
My rule of thumb,
If its not used get rid of it.
All surplus comments, attrributes are just noise and help your code to become unreadable. If left there they encourage more surplus code in your code base. So remove it.
I try to follow the YAGNI principle, so this bothers me as well.
Does it take even a minimal effort to read that additional (useless, as you added) code?
If yes (and I think it is so) then it should not be in the code. Code like this is polluted with extra snippets that are not useful, they are there "just in case".
The "later on refactoring" of these things can be painful, after 6 o 12 months, who is going to remember if that was really used?
Really don't like it.
Because I then spend valuable time trying to figure out why it's there. Assuming that if it's there, it's there for a reason, and if I don't see the reason, then there's a chance I'm missing something important that I should understand before I start messing with the code. It irritates me when I realize that I've just wasted an hour trying to understand why, or what, some snippet of code is doing, that was just left there by some developer too lazy to go back and remove it.
Useless one-liner code can and should be removed.
Useless code that took time to write can and should be removed...but people in charge tend to get queasy about this. Perhaps the best solution is to have a ProbablyUselessButWhoKnows project where everyone can check in pointless code that might be used again in two or three years. If nothing else, this way people don't have to feel nervous about deleting it.
(Yes, in theory you can get it out of source control, but old deleted code in source control is not exactly highly discoverable.)
In a commercial project - I'd say no, especially if someone can de-assemble it for reading and then has a WTF moment.
In a home-project - sure why not, I often keep some snippets for later use.
Well I can't comment this particular piece of code without knowing your background but I personally follow strictly a rule not to have anything in code unless I really need it. Or at least know that it may be useful some day for something I have in mind already now.
This is bad code.
Bad code is common practice.
That being said sometimes it is not worth the effort in changing stuff that isn't "broken".
It would seem that perfection is attained not when no more can be added, but when no more can be removed. — Antoine de Saint-Exupéry
Is think the meaning of useless is that it cannot and will not be used. I also think that an open door is very open.
If there is an active plan to use this additional feature, then keep it in.
If you know it will never be used, or if that plan stopped being relevant 6 months ago, then pull it out. I'd comment it out first, then remove it fully later.
I'm in the midst of rescoping a lot of variables that were public but really only need to be protected or private, simply because they don't make sense from an API perspective to be exposed--that and nothing uses them.
I'm running a refactoring code dojo for some coworkers who asked how refactoring and patterns go together, and I need a sample code base. Anyone know of a good starting point that isn't to horrible they can't make heads or tails of the code, but can rewrite their way to something useful?
I would actually suggesting refactoring some of your and your coworkers' code.
There are always places that an existing codebase can be refactored, and the familiarity with the existing code will help make it feel more like a useful thing and less like an exercise. Find something in your company's code to use as an example, if possible.
Here are some codes, both the original and the refactored version, so you can prepare your kata or simply compare the results once the refactoring is performed:
My books have both shorter examples and a longer, actually a book long example. Code is free to download.
VB Code Examples
C# Code Examples
A nice example from Refactoring Workbook
There are a lot of examples on the internet of simple games like Tic-Tac-Toe or Snake that have a lot of smells but are simple enough to start with refactoring.
The first chapter in Martin Fowler "Refactoring" is a good starting point to refactoring. I understood most of the concepts when one of my teachers at school used this example.
What is the general knowledge level of your coworkers?
Something basic as code duplication should be easy to wrap their heads around. Two pieces of (nearly) identical code that can be refactored into a reusable method, class, whatever. Using a (past) example from your own codebase would be good.
I would recommend you to develop a simple example project for a specific requirement.
Then you add one more requirement and make changes to the existing classes . You keep on doing this and show them how you are finding it difficult to make each change when the code is not designed properly. This will make them realize easily because, this is what those ppl will be doing in their day to day work. Make them realize that , if patterns and principles are not followed from beginning, how are they going to end up in mess at the end.
When they realize that,then you start from scratch or refactor the existing messed up code .Now add a requirement and make them realize that it is easy to make a change in the refactored code, so that you need to test only a few classes. One change would not affect others and so on.
You could use the computer ,keyboard and printer class as an example. Add requirements like, you will be wanting the computer to read from mouse , then one more requirement can be like your computer would want to save it in hard disk than printing. Finally your refactored code should be like, your computer class should depend on abstract input device class and output device class. And your keyboard class should inherit from Inputdevice class.
Clean Code: A Handbook of Agile Software Craftsmanship by Robert C. Martin considers refactoring.
I'm loving Refactoring Guru examples.
In there you can find design patterns examples too.
Refactoring is non-functional requirement when code perform correct functionality for which it is designed however difficult to debug, requires more effort to maintain and some performance bottleneck. Refactoring is to change to be easily maintainable, good readability and improve efficiency.
Thus we need to focus on criteria to make code more readable, easy to maintain.
Its obvious that having very large method/function might be difficult to understand.
Class depends on other hundreds of class make thing worst while debugging.
Code should be readable just like reading some workflow.
You can also use tools like sonar which can help you to identify critical criteria such as "Cyclomatic Complexity"
http://www.sonarsource.org/managing-cyclomatic-complexity-to-increase-maintainability/
You ask them to write code them self and check how tool does refactoring.
Apart from that, you can write code in eclipse and there is option available which does refactoring for you...
It's a bit dated (2003), but IBM has several refactoring examples (that work[ed?] in Eclipse) at http://www.ibm.com/developerworks/library/os-ecref/
Let's say you've inherited a C# codebase that uses one class with 200 static methods to provide core functionality (such as database lookups). Of the many nightmares in that class, there's copious use of Hungarian notation (the bad kind).
Would you refactor the variable names to remove the Hungarian notation, or would you leave them alone?
If you chose to change all the variables to remove Hungarian notation, what would be your method?
Refactor -- I find Hungarian notation on that scale really interferes with the natural readability of the code, and the exercise is a good way of getting familiar with what's there.
However, if there are other team members who know the code base you would need consensus on the refactoring, and if any of the variables are exposed outside of the one project then you will have to leave them alone.
Just leave it alone. There are better uses of your time.
Right click on the variable name, Refactor -> Rename.
There are VS add-ins that do this as well, but the built-in method works fine for me.
What would I do? Assuming that I just have to maintain the code and not rewrite it any significant way? Leave it well alone. And When I do add code, go with the existing style, meaning, use that ugly Hungarian notation (as dirty as that makes me feel.)
But, hey, if you really have a hankerin' fer refactorin' then just do a little at a time. Every time you work on it spend ten minutes renaming variables. Tidying things up a little. After a few months you might find it's clean as a whistle....
Don't forget that there are two kinds of Hungarian Notation.
The original Charles Simonyi HN, later known as App's Hungarian and the later abomination called System Hungarian after some peckerhead (it's a technical term) totally misread Simonyi's original paper.
Unfortunately, System HN was propagated by Petzold and others to become the more dominant abortion that it is rightfully recognised as today.
Read Joel's excellent article about the intent of the original Apps Hungarian Notation and be sorry for what got lost in the rush.
If what you've got is App's Hungarian you will probably want to keep it after reading both the original Charles Simonyi article and the Joel article.
If you've landed in a steaming pile of System Hungarian?
All bets are off!
Whew! (said while holding nose) (-:
if you're feeling lucky and just want the Hungarian to go away, isolate the Hungarian prefixes that are used and try a search and replace in file to replace them with nothing, then do a clean and rebuild. If the number of errors is small, just fix it. If the number of errors is huge, go back and break it up into logical (by domain) classes first, then rename individually (the IDE will help)
I used to use it religiously back in the VB6 days, but stopped when VB.NET came out because that's what the new VB guidelines said. Other developers didn't. So, we’ve got a lot of old code with it. When I do maintenance on code I remove the notation from the functions/methods/sub I touch. I wouldn't remove it all at once unless you've got really good unit tests for everything and can run them to prove that nothing's broken.
How much are you going to break by doing this? That's an important question to ask yourself. If there are a lot of other pieces of code that use that library, then you might just be creating work for folks (maybe you) by going through the renaming exercise.
I'd put it on the list of things to do when refactoring. At least then everyone expects you to be breaking the library (temporarily).
That said, I totally get frustrated with poorly named methods and variables, so I can relate.
I wouldn't make a project out of it. I'd use the refactoring tools in VS (actually, I'd use Resharper's, but VS's work just fine) and fix all the variables in any method I was called upon to modify. Or if I had to make larger-scale changes, I'd refactor the variable names in any method I was called upon to understand.
If you have a legitimate need to remove and change it I would use either the built in refactoring tools, or something like Resharper.
However, I would agree with Chris Conway to a certain standpoint and ask you WHY, yes, it is annoying, but at the same time, a lot of the time the "if it aint't broke done't fix it" method is really the best way to go!
Only change it when you directly use it. And make sure you have a testbench ready to apply to ensure it still works.
I agree that the best way to phase out hungarian notation is to refactor code as you modify it. The greatest benefit of doing this kind of refactoring is that you should be writing unit tests around the code you're modifying so that you have a safety net instead of crossing your fingers and hoping that you don't break existing functionality. Once you have these unit tests in place, you are free to change the code to your heart's content.
I'd say a bigger problem is that you have a single class with 200(!) methods!
If this is a much depended on / much changed class then it might be worth refactoring to make it more usable.
In this, Resharper is an absolute must (you could use the built in refactoring stuff, but Resharper is way better).
Start finding a group of related methods, and then refactor these out into a nice small cohesive class. Update to conform to your latest code standards.
Compile & run your test suite.
Have energy for more? Extract another class.
Worn out - no trouble; come back and do some more tomorrow. In just a few days you'll have conquered the beast.
I agree with #Booji -- do it manually, on a per-routine basis when you're already visiting the code for some other good reason. Then, you'll get the most common ones out of the way, and who cares about the rest.
I was thinking of asking a similar question, only in my case, the offending code is my own. I have a very old habit of using "the bad kind" of Hungarian from my FoxPro days (which had weak typing and unusual scoping) — a habit I've only recently kicked.
It's hard — it means accepting an inconsistent style in your code base. It was only a week ago I finally said "screw it" and began a parameter name without the letter "p". The cognitive dissonance I initially felt has given way to a feeling of liberty. The world did not come to an end.
The way I've been going about this problem is changing one variable at a time as I come across them, then perform more sweeping changes when you come back to do more in-depth changes. If you're anything like me, the different nomenclature of your variables will drive you bat-shiat crazy for a while, but you'll slowly become used to it. The key is to chip away at it a little bit at a time until you have everything to where it needs to be.
Alternatively, you could jettison your variables altogether and just have every function return 42.
It sounds to me like the bigger problem is that 200-method God Object class. I'd suggest that refactoring just to remove the Hungarian notation is a low-value, high-risk activity in of itself. Unless there's a copious set of automated unit tests around that class to give you some confidence in your refactoring, I think you should leave it well and truly alone.
I guess it's unlikely that such a set of tests exists, because a developer following TDD practices would (hopefully) have naturally avoided building a god object in the first place - it would be very difficult to write comprehensive tests for.
Eliminating the god object and getting a unit test base in place is of higher value, however. My advice would be to look for opportunities to refactor the class itself - perhaps when a suitable business requirement/change comes along that necessitates a change to that code (and thus hopefully comes with some system & regression testing bought and paid for). You might not be able to justify the effort of refactoring the whole thing in one go, but you can do it piece by piece as the opportunity comes along, and test-drive the changes. In this way you can slowly convert the spaghetti code into a cleaner code base with comprehensive unit tests, bit by bit.
And you can eliminate the Hungarian as you go, if you like.
I am actually doing the same thing here for an application extension. My approach has been to use VIM mappings to search for specific Hungarian notation prefixes and then delete them and fix capitalization as appropriate.
Examples (goes in vimrc):
"" Hungarian notation conversion helpers
"" get rid of str prefixes and fix caps e.g. strName -> name
map ,bs /\Wstr[A-Z]^Ml3x~
map ,bi /\Wint[A-Z]^Ml3x~
"" little more complex to clean up m_p type class variables
map ,bm /\Wm_p\?[A-Z]^M:.s/\(\W\)m_p\?/\1_/^M/\W_[A-Z]^Mll~
map ,bp /\Wp[A-Z]^Mlx~
If you're gonna break code just for the sake of refactoring, I would seriously consider leaving i alone, specially, if you are going to affect other people in your team who may be depending on that code.
If your team is OK with this refactoring, and investing your time in doing this (which may be a time-saver in the future, if it means the code is more readable/maintainable), use Visual Studio (or whatever IDE you are using) to help you refactor the code.
However, if a big change like this is not a risk your team/boss is willing to take, I would suggest a somewhat unorthodox, half-way approach. Instead of doing all your refactoring in a single sweep, why not refactor sections of code (more specifically, functions) that need to be touched during normal maintenance? Over time, this slow refactoring will bring the code up to a cleaner state, at which point you can finish the refactoring process with a final sweep.
Use this java tool to remove HN:
Or just use "replace"/"replace all" with regex like below to replace "c_strX" to "x":
I love Hungarian notation. Don't understand why you would want to get rid of it.
I just refactored some code that was in a different section of the class I was working on because it was a series of nested conditional operators (?:) that was made a ton clearer by a fairly simple switch statement (C#).
When will you touch code that isn't directly what you are working on to make it more clear?
I once was refactoring and came across something like this code:
string strMyString;
try
{
strMyString = Session["MySessionVar"].ToString();
}
catch
{
strMyString = "";
}
Resharper pointed out that the .ToString() was redundant, so I took it out. Unfortunately, that ended up breaking the code. Whenever MySessionVar was null, it wasn't causing the NullReferenceException that the code relied on to bump it down to the catch block. I know, this was some sad code. But I did learn a good lesson from it. Don't rapidly go through old code relying on a tool to help you do the refactoring - think it through yourself.
I did end up refactoring it as follows:
string strMyString = Session["MySessionVar"] ?? "";
Update: Since this post is being upvoted and technically doesn't contain an answer to the question, I figured I should actually answer the question. (Ok, it was bothering me to the point that I was actually dreaming about it.)
Personally I ask myself a few questions before refactoring.
1) Is the system under source control? If so, go ahead and refactor because you can always roll back if something breaks.
2) Do unit tests exist for the functionality I am altering? If so, great! Refactor. The danger here is that the existence of unit tests don't indicate the accuracy and scope of said unit tests. Good unit tests should pick up any breaking changes.
3) Do I thoroughly understand the code I am refactoring? If there's no source control and no tests and I don't really understand the code I am changing, that's a red flag. I'd need to get more comfortable with the code before refactoring.
In case #3 I would probably spend the time to actually track all of the code that is currently using the method I am refactoring. Depending on the scope of the code this could be easy or impossible (ie. if it's a public API). If it comes down to being a public API then you really need to understand the original intent of the code from a business perspective.
I only refactor it if tests are already in place. If not, it's usually not worth my time to write tests for and refactor presumably working code.
This is a small, minor antipattern but it so irritates me that whenever I find it, I expunge it immediately. In C (or C++ or Java)
if (p)
return true;
else
return false;
becomes
return p;
In Scheme,
(if p #t #f)
becomes
p
and in ML
if p then true else false
becomes
p
I see this antipattern almost exclusively in code written by undergraduate students. I am definitely not making this up!!
Whenever I come across it and I don't think changing it will cause problems (e.g. I can understand it enough that I know what it does. e.g. the level of voodoo is low).
I only bother to change it if there is some other reason I'm modifying the code.
How far I'm willing to take it depends on how confident I am that I won't break anything and how extensive my own changes to the code are going to be.
This is a great situation to show off the benefits of unit tests.
If unit tests are in place, developers can bravely and aggressively refactor oddly written code they might come across. If it passes the unit tests and you've increased readability, then you've done your good deed for the day and can move on.
Without unit tests, simplifying complex code that's filled with voodoo presents a great risk of breaking the code and not even knowing you've introduced a new bug! So most developers will take the cautious route and move on.
For simple refactoring I try to clean up deeply nested control structures and really long functions (more than one screen worth of text). However its not a great idea to refactor code without a good reason (especially in a big team of developers). In general, unless the refactoring will make a big improvement in the code or fix an egregious sin I try to leave well enough alone.
Not refactoring per-say but just as a matter of general housekeeping I generally do this stuff when I start work on a module:
Remove stupid comments
Comments that say nothing more than the function signature already says
Comments that are pure idiocy like "just what it looks like"
Changelogs at the top of the file (we have version control for a reason)
Any API docs that are clearly out-of-sync with the code
Remove commented-out chunks of code
Add version control tags like $Id$ if they are missing
Fix whitespace issues (this can be annoying to others though because your name shows up for a lot of lines in a diff even if all you did was change whitespace)
Remove whitespace at the end of the lines
Change tabs->spaces (for that is our convention where I work)
If the refactor makes the code much easier to read, the most common for me would be duplicate code, e.g. an if/else that only differs by the first/last commands.
if($something) {
load_data($something);
} else {
load_data($something);
echo "Loaded";
do_something_else();
}
More than (arguably) three or four lines of duplicate code always makes me think about refactoring. Also, I tend to move code around a lot, extracting the code I predict to be used more frequently into a separate place - a class with its own well-defined purpose and responsibilites, or a static method of a static class (usually placed in my Utils.* namespace).
But, to answer your question, yes, there are lot of cases when making the code shorter does not necessarily mean making it well structued and readable. Using the ?? operator in C# is another example. What you also have to think about are the new features in your language of choice - e.g. LINQ can be used to do some stuff in a very elegant manner but also can make a very simple thing very unreadable and overly complex. You need to weigh these two thing very carefully, in the end it all boils down to your personal taste and, mostly, experience.
Well, this is another "it depends" answer, but I am afraid it has to be.
I almost always break >2 similar conditionals into a switch... most often with regards to enums. I will short a return instead of a long statement.
ex:
if (condition) {
//lots of code
//returns value
} else {
return null;
}
becomes:
if (!condition)
return null;
//lots of code..
//return value
breaking out early reduces extra indents, and reduces long bits of code... also as a general rule I don't like methods with more than 10-15 lines of code. I like methods to have a singular purpose, even if creating more private methods internally.
Usually I don't refactor the code if I'm just browsing it, not actively working on it.
But sometimes ReSharper points out some stuff I just can't resist to Alt+Enter. :)
I tend to refactor very long functions and methods if I understand the set of inputs and outputs to a block.
This helps readability no end.
I would only refactor the code that I come across and am not actively working on after going through the following steps:
Speak with the author of the code (not always possible) to figure out what that piece of code does. Even if it is obvious to me as to what the piece of code is doing, it always helps to understand the rationale behind why the author may have decided to do something in a certain way. Spending a couple of minutes talking about it would not only help the original author understand your point of view, it also builds trust within the team.
Know or find out what that piece of code is doing in order to test it after re-factoring (A build process with unit tests is very helpful here. It makes the whole thing quick and easy). Run the unit tests before and after the change and ensure nothing is breaking due to your changes.
Send out a heads up to the team (if working with others) and let them know of the upcoming change so nobody is surprised when the change actually occurs
Refactoring for the sake of it is one of the roots of all evil. Please don't ever do it. (Unit tests do somewhat mitigate this).
Is vast swaths of commented out code an antipattern? While not code specifically, (it's comments) I see a lot of this kind of behaviour with people who don't understand how to use source control, and who want to keep the old code around for later so they can more easily go back if a bug was introduced. Whenever I see vast swaths of code that are commented out, I almost always remove them in their entirety.
I try to refactor based on following factors:
Do I understand enough to know whats happening?
Can I easily revert back if this change breaks the code.
Will I have enough time to revert the change back if it breaks the build.
And sometimes, if I have enough time, I refactor to learn. As in, I know my change may break the code, but I dont know where and how. So I change it anyways to find out where its breaking and why. That way I learn more about the code.
My domain has been mobile software (cell phones) where most of the code resides on my PC and wont impact others. Since I also maintain the CI build system for my company I can run a complete product build (for all phones) on the refactored code to ensure it doesnt break anything else. But thats my personal luxury which you may not have.
I tend to refactor global constants and enumerations quite a bit if they can be deemed a low refactor risk. Maybe it's just be, but something like a ClientAccountStatus enum should be in or close to the ClientAccount class rather than being in a GlobalConstAndEnum class.
Deletion/updating of comments which are clearly wrong or clearly pointless.
Removing them is:
safe
version control means you can find them again
improves the quality of the code to others and yourself
It is about the only 100% risk free refactoring I know.
Note that doing this in structured comments like javadoc comments is a different matter. Changing these is not risk free, as such they are very likely to be fixed/removed but not dead certain guaranteed fixes as standard incorrect code comments would be.