I have been trying to follow StyleCop's guidelines on a project, to see if the resulting code was better in the end. Most rules are reasonable or a matter of opinion on coding standard, but there is one rule which puzzles me, because I haven't seen anyone else recommend it, and because I don't see a clear benefit to it:
SA1101: The call to {method or property name} must begin with the 'this.' prefix to indicate that the item is a member of the class.
On the downside, the code is clearly more verbose that way, so what are the benefits of following that rule? Does anyone here follow that rule?
I don't really follow this guidance unless I'm in the scenarios you need it:
there is an actual ambiguity - mainly this impacts either constructors (this.name = name;) or things like Equals (return this.id == other.id;)
you want to pass a reference to the current instance
you want to call an extension method on the current instance
Other than that I consider this clutter. So I turn the rule off.
It can make code clearer at a glance. When you use this, it's easier to:
Tell static and instance members apart. (And distinguish instance methods from delegates.)
Distinguish instance members from local variables and parameters (without using a naming convention).
I think this article explains it a little
http://blogs.msdn.microsoft.com/sourceanalysis/archive/2008/05/25/a-difference-of-style.aspx
...a brilliant young developer at Microsoft (ok, it was me) decided to take it upon himself to write a little tool which could detect variances from the C# style used within his team. StyleCop was born. Over the next few years, we gathered up all of the C# style guidelines we could find from the various teams within Microsoft, and picked out all of best practices which were common to these styles. These formed the first set of StyleCop rules. One of the earliest rules that came out of this effort was the use of the this prefix to call out class members, and the removal of any underscore prefixes from field names. C# style had officially grown apart from its old C++ tribe.
this.This
this.Does
this.Not
this.Add
this.Clarity
this.Nor
this.Does
this.This
this.Add
this.Maintainability
this.To
this.Code
The usage of "this.", when used excessively or a forced style requirement, is nothing more then a contrivance used under the guise that there is < 1% of developers that really do not understand code or what they are doing, and makes it painful for 99% who want to write easily readable and maintainable code.
As soon as you start typing, Intellisence will list the content available in the scope of where you are typing, "this." is not necessary to expose class members, and unless you are completely clueless to what you are coding for you should be able to easily find the item you need.
Even if you are completely clueless, use "this." to hint what is available, but don't leave it in code. There are also a slew of add-ons like Resharper that help to bring clarity to the scope and expose the contents of objects more efficiently. It is better to learn how to use the tools provided to you then to develop a bad habit that is hated by a large number of your co-workers.
Any developer that does not inherently understand the scope of static, local, class or global content should not rely on "hints" to indicate the scope. "this." is worse then Hungarian notation as at least Hungarian notation provided an idea about the type the variable is referencing and serves some benefit. I would rather see "_" or "m" used to denote class field members then to see "this." everywhere.
I have never had an issue, nor seen an issue with a fellow developer that repeatedly fights with code scope or writes code that is always buggy because of not using "this." explicitly. It is an unwarranted fear that "this." prevents future code bugs and is often the argument used where ignorance is valued.
Coders grow with experience, "this." is like asking someone to put training wheels on their bike as an adult because it is what they first had to use to learn how to ride a bike. And adult might fall off a bike 1 in 1,000 times they get on it, but that is no reason to force them to use training wheels.
"this." should be banned from the language definition for C#, unfortunately there is only one reason for using it, and that is to resolve ambiguity, which could also be easily resolved through better code practices.
A few basic reasons for using this (and I coincidentally always prefix class values with the name of the class of which they are a part as well - even within the class itself).
1) Clarity. You know right this instant which variables you declared in the class definition and which you declared as locals, parameters and whatnot. In two years, you won't know that and you'll go on a wondrous voyage of re-discovery that is absolutely pointless and not required if you specifically state the parent up front. Somebody else working on your code has no idea from the get-go and thus benefits instantly.
2) Intellisense. If you type 'this.' you get all instance-specific members and properties in the help. It makes finding things a lot easier, especially if you're maintaining somebody else's code or code you haven't looked at in a couple of years. It also helps you avoid errors caused by misconceptions of what variables and methods are declared where and how. It can help you discover errors that otherwise wouldn't show up until the compiler choked on your code.
3) Granted you can achieve the same effect by using prefixes and other techniques, but this begs the question of why you would invent a mechanism to handle a problem when there is a mechanism to do so built into the language that is actually supported by the IDE? If you touch-type, even in part, it will ultimately reduce your error rate, too, by not forcing you to take your fingers out of the home position to get to the underscore key.
I see lots of young programmers who make a big deal out of the time they will save by not typing a character or two. Most of your time will be spent debugging, not coding. Don't worry so much about your typing speed. Worry more about how quickly you can understand what is going on in the code. If you save a total of five minutes coding and win up spending an extra ten minutes debugging, you've slowed yourself down, no matter how fast you look like you're going.
Note that the compiler doesn't care whether you prefix references with this or not (unless there's a name collision with a local variable and a field or you want to call an extension method on the current instance.)
It's up to your style. Personally I remove this. from code as I think it decreases the signal to noise ratio.
Just because Microsoft uses this style internally doesn't mean you have to. StyleCop seems to be a MS-internal tool gone public. I'm all for adhering to the Microsoft conventions around public things, such as:
type names are in PascalCase
parameter names are in camelCase
interfaces should be prefixed with the letter I
use singular names for enums, except for when they're [Flags]
...but what happens in the private realms of your code is, well, private. Do whatever your team agrees upon.
Consistency is also important. It reduces cognitive load when reading code, especially if the code style is as you expect it. But even when dealing with a foreign coding style, if it's consistent then it won't take long to become used to it. Use tools like ReSharper and StyleCop to ensure consistency where you think it's important.
Using .NET Reflector suggests that Microsoft isn't that great at adhering to the StyleCop coding standards in the BCL anyway.
I do follow it, because I think it's really convenient to be able to tell apart access to static and instance members at first glance.
And of course I have to use it in my constructors, because I normally give the constructor parameters the same names as the field their values get assigned to. So I need "this" to access the fields.
In addition it is possible to duplicate variable names in a function so using 'this' can make it clearer.
class foo {
private string aString;
public void SetString(string aString){
//this.aString refers to the class field
//aString refers to the method parameter
this.aString = aString;
}
}
I follow it mainly for intellisense reasons. It is so nice typing this. and getting a consise list of properties, methods, etc.
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I've never been a fan of Hungarian notation, I've always found it pretty useless unless you're doing some really low level programming, but in every C++ project I've worked on some kind of Hungarian notation policy was enforced, and with it the use of some 'not-really-Hungarian' prefixes as m_ for fields, s_ for statics, g_ for globals and so on.
Soon I realized how much useless it was in C# and gradually started to drop all of my old habits... but the 'm_' thing. I still use the m_ prefix on private fields because I really find it very useful to being able to distinguish between parameters, locals and fields.
The naming conventions for fields page at MSDN says I shouldn't, but it does not say why (the way e.g. Google's conventions generally tend to rationalize their prescriptions).
Are there reasons why I shouldn't or is it only a matter of style. If it is the latter, are prefixes generally considered a bad style and can I expect negative reactions from other people working on the codebase?
I like the underbar prefix for member fields. Mostly I like it because that way, all of my member fields are shown alphabetically before my methods in the wizard bar at the top of the screen.
When you should:
When your project coding guidelines say you should
When you shouldn't:
When your project coding guidelines say you shouldn't
If you don't have any guidelines yet, you're free to choose whatever you or your team want and feel most comfortable with. Personally when coding C++ I tend to use m_ for members, it does help. When coding in other languages, particularly those without true classes (like Javascript, Lua) I don't.
In short I don't believe there is a "right" and a "wrong" way.
The auto-implemented property feature in C# 3.0 creates less of a need for this convention one way or the other. Instead of writing
string m_name;
public string Name { get { return m_name; } }
or
string _Name;
public string Name { get { return _Name; } }
(or any other convention), you can now write
public string Name { get; private set; }
Since you no longer need the explicit backing store variable, you no longer have to come up with a name for it; thus avoiding this entire discussion.
Obviously, this argument doesn't apply when you really need explicit backing store such as to perform validation.
As some have alluded to, the MS guidelines say:
Do not use a prefix for field names.
For example, do not use g_ or s_ to
distinguish static versus non-static
fields.
I happen to agree with this. prefixes make your code look ugly and waste space with inconsequential characters. Having said that, it is often common to use fields to back properties where both the field and the property would have the same name (with the private field being camel case and the property being pascal case). In VB, this doesn't work, since VB isn't case-sensitive. In this scenario, I recommend the use of a single _ prefix. No more, no less. It just looks cleaner, IMHO.
I have experimented with m_, s_, just _, and no prefix at all. I have settled on using just _ for all static and instance variables. I don't find it important to distinguish static variables from instance variables. In theory it sounds good, in practice it doesn't create a problem.
A coworker once made a convincing argument to eliminate all prefixes, we tried it on one project and it worked better then I expected. I carried it forward to my next project and became annoyed that it "interferes" with Intellisense. When you have the following situation
int foo;
public int Foo
{
get { return foo; }
}
Starting to type foo will suggest both the instance variable and the property. Prefixing the variable with an underscore eliminates the annoying double suggestion, so I switched back to using just _.
I try to follow the MSDN .NET library guidelines. They include a naming guidelines section.
Obviously, these are secondary to your project guidelines.
I prefer to mark property backing fields (although as already mentioned .NET 3.0+ reduces the need thanks to Automatic Properties) with underscores but not the "m". For one it puts them at the top of the InteliSense list when I come to use them.
I will admit that I need to brush-up on the guidelines on MSDN, things can change so quickly these days.
With tools like resharper there's really no reason for prefixes. Also if you write short methods, you should be able to tell really quickly where the var is coming from. Finally, I guess I wouldn't really see the need to tell a difference between a static or not because again resharper is going to red line it if you try to do something you're not able to. Even without resharper you're probably saved by the compiler.
I always prefix member variables with m_ and static variables with s_ for the same reasons that you state. Some people prefix member variables with an underscore, but I've always found this a bit odd looking (but that's just a personal preference).
Most people I work with use the m_/s_ prefix. I don't really think it matters too much what you use, as long as you're consistent.
I never use them. It encourages sloppy coding.
The MSDN coding guidelines, that's where it's at.
Here are a few reasons to use _ (and not m_).
(1) Many BCL guys do it despite MS's naming guide. (Check out their blog.) Those guys write the framework, so they have some good habits worth copying. Some of the most helpful example code on MSDN is written by them, and so uses the underscore convention. It's a de-facto industry standard.
(2) A single underscore is a noticeable yet unobtrusive way to disambiguate method and class-level variables by simply reading the source. It helps people understand new (or old) code at-a-glance when reading it. Yes, you can mouse-over to see this in an IDE, but we shouldn't be forced to. You may want to read it in a text editor, or dare I say it, on paper.
(3) Some say you don't need any prefix as methods will be short, and later if needed you can change the field to an auto-implemented property. But in the real world methods are as long as they need to be, and there are important differences between fields and properties (e.g. serialization and initialization).
Footnote: The "m" for member in m_ is redundant in our usage here, but it was lower case because one of the ideas in many of these old naming conventions was that type names started with upper case and instance names started with lower case. That doesn't apply in .NET so it's doubly redundant. Also Hungarian notation was sometimes useful with old C compilers (e.g. integer or pointer casting and arithmetic) but even in C++ its usefulness was diminished when dealing with classes.
As #John Kraft mentions, there is no "correct" answer. MattJ is the closest–you should always follow your company's style guidelines. When in Rome, and all that.
As for my personal opinion, since it's called for here, I vote that you drop m_ entirely.
I believe the best style is one where all members are PascalCased, regardless of visibility (that means even private members), and all arguments are camelCased. I do not break this style.
I can understand the desire to prefix property backing store field; after all you must differentiate between the field and the property, right? I agree, you must. But use a post-fix.
Instead of m_MyProperty (or even _MyProperty, which I've seen and even promoted once upon a time), use MyPropertyValue. It's easier to read and understand and -- more importantly -- it's close to your original property name in intellisense.
Ultimately, that's the reason I prefer a postfix. If I want to access MyPropertyValue using intellisense you (typically) type "My <down-arrow> <tab>", since by then you're close enough that only MyProperty and MyPropertyValue are on the list. If you want to access m_MyProperty using intellisense, you'll have to type "m_My <tab>".
It's about keystroke economy, in my opinion.
There is one important difference between C++ and C#: Tool support. When you follow the established guidelines (or common variations), you will get a deep level of tool support that C++ never had. Following the standards allows tools to do deeper refactoring/rename operations than you'd otherwise be capable of. Resharper does this. So stick with one of the established standards.
I never do this and the reason why is that I [try to] keep my methods short. If I can see the whole method on the screen, I can see the params, I can see the locals and so I can tell what is owned by the class and what is a param or a local.
I do typically name my params and locals using a particular notation, but not always. I'm nothing if not inconsistent. I rely on the fact that my methods are short and try to keep them from doing X, Y and Z when they should be only doing X.
Anyhow, that's my two cents.
Unless I'm stuck with vi or Emacs for editing code, my IDE takes care of differential display of members for me so I rarely uses any special conventions. That also goes for prefixing interfaces with I or classes with C.
Someone, please, explain the .NET style of I-prefix on interfaces. :)
what i am used to is that private properties got small underscone f.ex "string _name". the public one got "Name". and the input variables in methods got small letter"void MyMethod(string name)".
if you got static const is often written with big letters. static const MYCONST = "hmpf".
I am sure that I will get flamed for this but so be it.
It's called Microsoft's .NET library guidelines but it's really Brad Abrams's views (document here) - there are other views with valid reasons.
People tend to go with the majority view rather than having good solid reasons for a specific style.
The important point is to evaluate why a specific style is used and why it's preferred over another style - in other words, have a reason for choosing a style not just because everyone says it's the thing to do - think for yourself.
The basic reason for not using old style Hungarian was the use of abbreviations which was different for every team and difficult to learn - this is easily solved by not abbreviating.
As the available development tools change the style should change to what makes the most sense - but have a solid reason for each style item.
Below are my style guidelines with my reasons - I am always looking for ways to improve my style to create more reliable and easier to maintain code.
Variable Naming Convention
We all have our view on variable naming conventions. There are many different styles that will help produce easily maintainable quality code - any style which supports the basic essential information about a variable are okay. The criteria for a specific naming convention should be that it aids in producing code that is reliable and easily maintainable. Criteria that should not be used are:
It's ugly
Microsoft (i.e. Brad Abrams) says don't use that style - Microsoft does not always produce the most reliable code just look at the bugs in Expression Blend.
It is very important when reading code that a variable name should instantly convey three essential facts about the variable:
it’s scope
it’s type
a clearly understand about what it is used for
Scope: Microsoft recommends relying totally on IntelliSense . IntelliSense is awesome; however, one simply does not mouse over every variable to see it's scope and type. Assuming a variable is in a scope that it is not can cause significant errors. For example, if a reference variable is passed in as a parameter and it is altered in local scope that change will remain after the method returns which may not be desired. If a field or a static variable is modified in local scope but one thinks that it is a local variable unexpected behavior could result. Therefore it is extremely important to be able to just look at a variable (not mouse over) and instantly know it's scope.
The following style for indicating scope is suggested; however, any style is perfectly okay as long as it clearly and consistently indicates the variable's scope:
m_ field variable
p_ parameter passed to a method
s_ static variable
local variable
Type: Serious errors can occur if one believes they are working with a specific type when they are actually working with a different type - again, we simply do not mouse over ever variable to determine its type, we just assume that we know what its type is and that is how errors are created.
Abbreviations: Abbreviations are evil because they can mean different things to different developers. One developer may think a leading lower case "s" means string while another may think it means signed integer. Abbreviations are a sign of lazy coding - take a little extra time and type the full name to make it clear to the developer that has to maintain the code. For example, the difference between "str" and "string" is only three characters - it does not take much more effort to make code easy to maintain.
Common and clear abbreviations for built-in data types only are acceptable but must be standardized within the team.
Self Documenting Code: Adding a clear description to a variable name makes it very easy for another developer to read and understand the code - make the name so understandable that the team manager can read and understand the code without being a developer.
Order of Variable Name Parts: The recommended order is scope-type-description because:
IntelliSense will group all similar scopes and within each scope IntelliSense will group all similar types which makes lookups easy - try finding a variable the other way
It makes it very easy to see and understand the scope and to see and understand the type
It's a fairly common style and easy to understand
It will pass FxCop
Examples: Here are a few examples:
m_stringCustomerName
p_stringCustomerDatabaseConnectionString
intNumberOfCustomerRecords or iNumberOfCustomerRecords or integerNumberOfCustomerRecords
These simple rules will significantly improve code reliability and maintainability.
Control Structure Single Line Statements
All control structures (if, while, for, etc.) single line statements should always be wrapped with braces because it is very easy to add a new statement not realizing that a given statement belongs to a control structure which will break the code logic without generating any compile time errors.
Method Exception Wrapping
All methods should be wrapped with an outer try-catch which trap, provide a place to recover, identify, locate, log, and make a decision to throw or not. It is the unexpected exception that cause our applications to crash - by wrapping every method trapping all unhandled exceptions we guarantee identifying and logging all exceptions and we prevent our application from ever crashing. It takes a little more work but the results is well worth the effort.
Indentation
Indentation is not a major issue; however, four spaces and not using tabs is suggested. If code is printed, the first printer tab usually defaults to 8 spaces. Different developer tend to use different tab sizes. Microsoft's code is usually indented 4 space so if one uses any Microsoft code and uses other than 4 spaces, then the code will need to be reformatted. Four spaces makes it easy and consistent.
I never use any hungarian warts whenever I'm given the choice. It's extra typing and doesn't convey any meaningful information. Any good IDE (and I define "good" based on the presence of this feature, among others) will allow you to have different syntax highlighting for static members, instance members, member functions, types, etc. There is no reason to clutter your code with information that can be provided by the IDE. This is a corollary to not cluttering your code with commented-out old code because your versioning system should be responsible for that stuff.
The best way is to agree on a standard with your colleagues, and stick to it. It doesn't absolutely have to be the method that would work best for everyone, just agreeing on one method is more important than which method you actually agree on.
What we chose for our code standard is to use _ as prefix for member variables. One of the reasons was that it makes it easy to find the local variables in the intellisense.
Before we agreed on that standard I used another one. I didn't use any prefix at all, and wrote this.memberVariable in the code to show that I was using a member variable.
With the property shorthand in C# 3, I find that I use a lot less explicit member variables.
The closest thing to official guidelines is StyleCop, a tool from Microsoft which can automatically analyse your source files and detect violations from the recommended coding style, and can be run from within Visual Studio and/or automated builds such as MSBuild.
We use it on our projects and it does help to make code style and layout more consistent between developers, although be warned it does take quite a bit of getting used to!
To answer your question - it doesn't allow any Hungarian notation, nor any prefixes like m_ (in fact, it doesn't allow the use of underscores at all).
I don't use that style any longer. It was developed to help you see quickly how variables were being used. The newer dev environments let you see that information by hovering your mouse over the variable. The need for it has gone away if you use those newer tools.
There might also be some insight to be gleaned from C++ Coding Standards (Sutter, Herb and Alexandrescum Andrei, 2004). Item #0 is entitled "Don't sweat the small stuff. (Or: Know what not to standardize.)".
They touch on this specific question a little bit by saying "If you can't decide on your own naming convention, try ... private member variables likeThis_ ..." (Remember use of leading underscore is subject to very specific rules in C++).
However, before getting there, they emphasize a certain level of consistency "...the important thing is not to set a rule but just to be consistent with the style already in use within the file..."
The benefit of that notation in C/C++ was to make it easier to see what a symbol's type was without having to go search for the declaration. These styles appeared before the arrival of Intellisense and "Go to Definition" - we often had to go on a goose chase looking for the declaration in who knows how many header files. On a large project this could be a significant annoyance which was bad enough when looking at C source code, but even worse when doing forensics using mixed assembly+source code and a raw call stack.
When faced with these realities, using m_ and all the other hungarian rules starts to make some sense even with the maintenance overhead because of how much time it would save just in looking up a symbol's type when looking at unfamiliar code. Now of course we have Intellisense and "Go to Definition", so the main time saving motivation of that naming convention is no longer there. I don't think there's much point in doing that any more, and I generally try to go with the .NET library guidelines just to be consistent and possibly gain a little bit more tool support.
If you are not coding under a particular guideline, you should keep using your actual m_ notation and change it if the project coding guidelines says so.
Be functional.
Do not use global variables.
Do not use static variables.
Do not use member variables.
If you really have to, but only if you really have to, use one and only one variable to access your application / environment.
I'm wondering if there are any reasons (apart from tidying up source code) why developers use the "Remove Unused Usings" feature in Visual Studio 2008?
There are a few reasons you'd want to take them out.
It's pointless. They add no value.
It's confusing. What is being used from that namespace?
If you don't, then you'll gradually accumulate pointless using statements as your code changes over time.
Static analysis is slower.
Code compilation is slower.
On the other hand, there aren't many reasons to leave them in. I suppose you save yourself the effort of having to delete them. But if you're that lazy, you've got bigger problems!
I would say quite the contrary - it's extremely helpful to remove unneeded, unnecessary using statements.
Imagine you have to go back to your code in 3, 6, 9 months - or someone else has to take over your code and maintain it.
If you have a huge long laundry list of using statement that aren't really needed, looking at the code could be quite confusing. Why is that using in there, if nothing is used from that namespace??
I guess in terms of long-term maintainability in a professional environment, I'd strongly suggest to keep your code as clean as possible - and that includes dumping unnecessary stuff from it. Less clutter equals less confusion and thus higher maintainability.
Marc
In addition to the reasons already given, it prevents unnecessary naming conflicts. Consider this file:
using System.IO;
using System.Windows.Shapes;
namespace LicenseTester
{
public static class Example
{
private static string temporaryPath = Path.GetTempFileName();
}
}
This code doesn't compile because both the namespaces System.IO and System.Windows.Shapes each contain a class called Path. We could fix it by using the full class path,
private static string temporaryPath = System.IO.Path.GetTempFileName();
or we could simply remove the line using System.Windows.Shapes;.
This seems to me to be a very sensible question, which is being treated in quite a flippant way by the people responding.
I'd say that any change to source code needs to be justified. These changes can have hidden costs, and the person posing the question wanted to be made aware of this. They didn't ask to be called "lazy", as one person inimated.
I have just started using ReSharper, and it is starting to give warnings and style hints on the project I am responsible for. Amongst them is the removal of redundant using directive, but also redundant qualifiers, capitalisation and many more. My gut instinct is to tidy the code and resolve all hints, but my business head warns me against unjustified changes.
We use an automated build process, and therefore any change to our SVN repository would generate changes that we couldn't link to projects/bugs/issues, and would trigger automated builds and releases which delivered no functional change to previous versions.
If we look at the removal of redundant qualifiers, this could possibly cause confusion to developers as classes in our Domain and Data layers are only differentiated by the qualifiers.
If I look at the proper use of capitalisation of anachronyms (i.e. ABCD -> Abcd), then I have to take into account that ReSharper doesn't refactor any of the Xml files we use that reference class names.
So, following these hints is not as straight-forward as it appears, and should be treated with respect.
Less options in the IntelliSense popup (particularly if the namespaces contain lots of Extension methods).
Theoretically IntelliSense should be faster too.
Remove them. Less code to look at and wonder about saves time and confusion. I wish more people would KEEP THINGS SIMPLE, NEAT and TIDY.
It's like having dirty shirts and pants in your room. It's ugly and you have to wonder why it's there.
Code compiles quicker.
Recently I got another reason why deleting unused imports is quite helpful and important.
Imagine you have two assemblies, where one references the other (for now let´s call the first one A and the referenced B). Now when you have code in A that depends on B everything is fine. However at some stage in your development-process you notice that you actually don´t need that code any more but you leave the using-statement where it was. Now you not only have a meaningless using-directive but also an assembly-reference to B which is not used anywhere but in the obsolete directive. This firstly increases the amount of time needed for compiling A, as B has to be loaded also.
So this is not only an issue on cleaner and easier to read code but also on maintaining assembly-references in production-code where not all of those referenced assemblies even exist.
Finally in our exapmle we had to ship B and A together, although B is not used anywhere in A but in the using-section. This will massively affect the runtime-performance of A when loading the assembly.
It also helps prevent false circular dependencies, assuming you are also able to remove some dll/project references from your project after removing the unused usings.
At least in theory, if you were given a C# .cs file (or any single program source code file), you should be able to look at the code and create an environment that simulates everything it needs. With some compiling/parsing technique, you may even create a tool to do it automatically. If this is done by you at least in mind, you can ensure you understand everything that code file says.
Now consider, if you were given a .cs file with 1000 using directives which only 10 was actually used. Whenever you look at a symbol that is newly introduced in the code that references the outside world, you will have to go through those 1000 lines to figure out what it is. This obviously slows down the above procedure. So if you can reduce them to 10, it will help!
In my opinion, the C# using directive is very very weak, since you cannot specify single generic symbol without genericity being lost, and you cannot use using alias directive to use extension methods. This is not the case in other languages like Java, Python and Haskell, in those languages you are able to specify (almost) exactly what you want from the outside world. But even then, I will suggest to use using alias whenever possible.