C# 4.0
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S. Senthil Kumar wrote:
The methods themselves would have to be declared const, just like in C++.
Yeah, I wrote that myself, without reading your post. :doh:
S. Senthil Kumar wrote:
if a method declared const in v1 of the library became non const in v2, the "constness" guarantee will get broken (unless there is a runtime check).
I'm not sure I understand, could you please explain?
Cheers, Vıkram.
"You idiot British surprise me that your generators which grew up after Mid 50s had no brain at all." - Adnan Siddiqi.
Let's say you are using a library with the following code
// Assembly SomeLib.dll
class C
{
void someMethod() const {...}
}and the code using it looks like this
// Assembly App.exe
void usingMethod(const C obj)
{
obj.someMethod(); // ok, because someMethod is const
}Now let's say a new version of SomeLib.dll comes out and in that version, someMethod() becomes non-const. With C++, App.exe would require recompiling with the modified header file, and the compiler would be able to flag the error in
usingMethod(non const method call on a const object). With .NET and binary compatibility, there's no recompiling necessary - you just drop in the new DLL and now the const guarantee is broken. It would be a silent breaking change, unless there is a runtime check.Regards Senthil [MVP - Visual C#] _____________________________ My Home Page |My Blog | My Articles | My Flickr | WinMacro
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There are so many things wrong with extension methods that I *still* get baffled how the geniuses at M$ included that as a feature. I guess LINQ must have been a HUGE thing for every team to bend their libraries and languages to 'force' it to fit in. I just want the option not to use it or make me use it in the "good way". This is just like the way you could set option strict in classic VB. Luckily almost all Microsoft extension methods come with in their exclusive namespaces. So all I have to do now is not include those namespaces BUT that doesn't prevent some other genius at XYZ company to pack extension methods with regular methods in their libraries and forcing ME to write bad code. Chip on my shoulder :)
Sunny Ahuwanya "The beauty of the desert is that it hides a well somewhere" -- Antoine de Saint Exupéry
Sunny Ahuwanya wrote:
There are so many things wrong with extension methods
Care to list some of them? I get that they can pollute the list of methods in a class and can cause calls to unintended methods, what else do you find wrong?
Regards Senthil [MVP - Visual C#] _____________________________ My Home Page |My Blog | My Articles | My Flickr | WinMacro
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Pawel Krakowiak wrote:
I think of them as of an improvement and use them. Smile
Can anyone explain to me how extension methods are an improvement? Besides helping to sell LINQ and encouraging programmers to write code in a non-portable, non object oriented manner, what is the point of extension methods?
Sunny Ahuwanya "The beauty of the desert is that it hides a well somewhere" -- Antoine de Saint Exupéry
Sunny Ahuwanya wrote:
non-portable, non object oriented manner
Hmm, that's interesting. Is it not part of the ECMA spec? Considering there's no runtime support required for extension methods, I can't see any other portability concerns. Or maybe you are considering them non-portable because the calling code won't compile without the presence of the source code containing the extension methods? And yeah, they are non object oriented if you consider static methods in a static class non-object oriented as well.
Regards Senthil [MVP - Visual C#] _____________________________ My Home Page |My Blog | My Articles | My Flickr | WinMacro
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So now that C# 4.0 is being talked about, I was wondering what people thought would be good additions to the language. Sorry if this is a repost, but I went through several pages, and didn't see anything, so... What I'd frankly love to see would be tuples. Rather than having to use multiple 'out' parameters, you'd just return multiple values:
public int,int MinMax(int[] numbers)
{
int min, max;
// Code to calculate min/maxreturn min, max;
}What do you think? What would be good for the next version?
Kyosa Jamie Nordmeyer - Taekwondo Yi (2nd) Dan Portland, Oregon, USA
I don't know what I'd put in, but I know what I'd 'take out'. I'd restrict the use of the 'var' keyword to the Linq domain, only. I see major abuse coming, and I don't relish maintaining code which uses the 'var' keyword in a profligate fashion. D. T. Doutel
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So now that C# 4.0 is being talked about, I was wondering what people thought would be good additions to the language. Sorry if this is a repost, but I went through several pages, and didn't see anything, so... What I'd frankly love to see would be tuples. Rather than having to use multiple 'out' parameters, you'd just return multiple values:
public int,int MinMax(int[] numbers)
{
int min, max;
// Code to calculate min/maxreturn min, max;
}What do you think? What would be good for the next version?
Kyosa Jamie Nordmeyer - Taekwondo Yi (2nd) Dan Portland, Oregon, USA
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Sunny Ahuwanya wrote:
A good programming language need not be updated every three years.
True... but we're talking about C#. :-\ </cheapshot>
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You're right. These facts that you've laid out totally contradict the wild ramblings that I pulled off the back of cornflakes packets.
C# is only a prototype to find out what people want, the next language will take those concepts and be the "real" product. :-D
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How about a way to check against all values in an array or enumerabale at once with perhaps the keyword 'any' like below.
int[] supportedValues = new int[] { 3, 4, 5 }
int x = 4;if (x == any supportedValues)
{
// Do something.
}Instead of:
int[] supportedValues = new int[] { 3, 4, 5 }
int x = 4;
bool xIsSupported = false;foreach (int value in supportedValues)
{
if (x == value)
xIsSupported = true;
}if (xIsSupported)
{
// Do something.
}Good idea?
foreach (int value in supportedValues) { if (x == value) { xIsSupported = true; break; //why keep on when you are done? :confused: } }
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So now that C# 4.0 is being talked about, I was wondering what people thought would be good additions to the language. Sorry if this is a repost, but I went through several pages, and didn't see anything, so... What I'd frankly love to see would be tuples. Rather than having to use multiple 'out' parameters, you'd just return multiple values:
public int,int MinMax(int[] numbers)
{
int min, max;
// Code to calculate min/maxreturn min, max;
}What do you think? What would be good for the next version?
Kyosa Jamie Nordmeyer - Taekwondo Yi (2nd) Dan Portland, Oregon, USA
What every language needs, and what every virtual language lacks: the ability to do inline assembly where necessary with the understanding that makes your code non-portable. For some stupid reason, I'm currently working on a project that is testing hardware at a very low (sometimes pre-boot) level- but the primary languages seem to be VB.NET and C#. It's highly frustrating. I realize this would be dangerous and that most programmers out there aren't at a level where they could make proper use of it, but having NO capability for it is ridiculous.
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There are so many things wrong with extension methods that I *still* get baffled how the geniuses at M$ included that as a feature. I guess LINQ must have been a HUGE thing for every team to bend their libraries and languages to 'force' it to fit in. I just want the option not to use it or make me use it in the "good way". This is just like the way you could set option strict in classic VB. Luckily almost all Microsoft extension methods come with in their exclusive namespaces. So all I have to do now is not include those namespaces BUT that doesn't prevent some other genius at XYZ company to pack extension methods with regular methods in their libraries and forcing ME to write bad code. Chip on my shoulder :)
Sunny Ahuwanya "The beauty of the desert is that it hides a well somewhere" -- Antoine de Saint Exupéry
Yeah, a bad idea implemented poorly. What I finally decided to do was to put each Extension Method I write (I have four, none of them Earth-shattering) in its own namespace, so you only get what you ask for. I don't use Linq either. The only reason to use .net 3.5 is HashSet, and even that is underwhelming -- no operators! I'm guessing they only added it because they use it in Linq and didn't want to be accused of using undocumented features (again).
Sunny Ahuwanya wrote:
forcing ME to write bad code.
Use them as regular static methods.
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Then so be it, in this case you would simply remove the "const" if it were there, meaning that it shouldn't really have been there to start with
Can you remove the code if you have to satisfy an interface definition that contains the const keyword? ;)
I've heard more said about less.
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Sunny Ahuwanya wrote:
non-portable, non object oriented manner
Hmm, that's interesting. Is it not part of the ECMA spec? Considering there's no runtime support required for extension methods, I can't see any other portability concerns. Or maybe you are considering them non-portable because the calling code won't compile without the presence of the source code containing the extension methods? And yeah, they are non object oriented if you consider static methods in a static class non-object oriented as well.
Regards Senthil [MVP - Visual C#] _____________________________ My Home Page |My Blog | My Articles | My Flickr | WinMacro
On Portability: 1) Imagine if I had to port some C# code from one framework/platform to another. Before C# 3.0, I'd had to make sure I have compatible libraries in the new framework. But now, I also have the added headache of figuring out where ALL the referenced extension methods in the code are and make sure they exist in the new framework (or write equivalent ones). It doesn't help that extension methods share the same dot notation with regular methods. I can't tell what an extension method is just by looking at the call. I'd have to write some tool that will check all referenced assemblies to point out the extension methods in the code. 2) Let's say I'm using LINQ's IEnumerable.Where extension method on a collection class someone else wrote, BUT I didn't realize the other developer had included a .Where regular method that returns an IEnumerable. My code will compile superbly without any warnings. The best part is that this code will work for months until THE CONDITION that differentiates the developer's .Where method and the LINQ's .Where method occurs. On Object Orientedness: Developer A uses List.SingleOrDefault() extensively, developer B creates a new class derived from List but would like .SingleOrDefault() to work a little differently so that all the pre-existing code will work properly with objects derived from his new class. He's stuck. :(
Sunny Ahuwanya "The beauty of the desert is that it hides a well somewhere" -- Antoine de Saint Exupéry
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Can you remove the code if you have to satisfy an interface definition that contains the const keyword? ;)
I've heard more said about less.
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I don't know what I'd put in, but I know what I'd 'take out'. I'd restrict the use of the 'var' keyword to the Linq domain, only. I see major abuse coming, and I don't relish maintaining code which uses the 'var' keyword in a profligate fashion. D. T. Doutel
Here here!
varshould only be used when you don't know the type! -
I'd really really really like to see absolutely no changes whatsoever. Seriously.
"It's so simple to be wise. Just think of something stupid to say and then don't say it." -Sam Levenson
I'd want to back up half a step.
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How about the ability to partially set array values. For example, for an int array of length 10 with default values of 0..9 respectively, the following would be valid:
myArray[3..5] = (-3, -4, -5);
The contents would then be: 0, 1, 2, -3, -4, -5, 6, 7, 8, 9 Another idea is a composite Label (say Strings and Images). The display of CompositeLabel.Text would display a String followed by an Image then we could have things (using my mythical System.Text.SmileyFace namespace) like . . .
myCompositeLabel.Text = "Hello, World " + System.Text.SmileyFace.BigGrin.ToImage();
The display would then be: Hello, World :-D Anthony
Reminds me of array slices in D, but that may be different.
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harold aptroot wrote:
Sure, edit the interface
:laugh: :laugh: :laugh: And when its in a third party assembly? Are you proposing to decompile it through reflection, edit, then rebuild it to use just to omit the const? And if its obfuscated?
I've heard more said about less.
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I bet 99% of you disagree with this one! I would like to see multiple inheritance and full operator overloading available in C#.
alan.cooper wrote:
multiple inheritance
Yes, or at least mixins. It's my foot and I'll blow it off if I want. :-D
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How about a way to check against all values in an array or enumerabale at once with perhaps the keyword 'any' like below.
int[] supportedValues = new int[] { 3, 4, 5 }
int x = 4;if (x == any supportedValues)
{
// Do something.
}Instead of:
int[] supportedValues = new int[] { 3, 4, 5 }
int x = 4;
bool xIsSupported = false;foreach (int value in supportedValues)
{
if (x == value)
xIsSupported = true;
}if (xIsSupported)
{
// Do something.
}Good idea?
Use a HashSet instead of an array.
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Sunny Ahuwanya wrote:
There are so many things wrong with extension methods
Care to list some of them? I get that they can pollute the list of methods in a class and can cause calls to unintended methods, what else do you find wrong?
Regards Senthil [MVP - Visual C#] _____________________________ My Home Page |My Blog | My Articles | My Flickr | WinMacro
S. Senthil Kumar wrote:
I get that they can pollute the list of methods in a class and can cause calls to unintended methods
BINGO!! Someone finally said it. Extension methods should come with a warning label. If you search the blogosphere, you'll see developers talking about how GREAT extension methods are and how they are going to add these great "extensions" that they always wanted to the classes that came with the class library. Imagine if I'm a newbie C# programmer and I want to perform a lot of strings to base64 encoded strings. I could create a static method and call that often, I could create a new class that has an implicit string operator that will perform the conversion or I could simply extend the string class? Which do you think I'd choose?
Sunny Ahuwanya "The beauty of the desert is that it hides a well somewhere" -- Antoine de Saint Exupéry
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S. Senthil Kumar wrote:
I get that they can pollute the list of methods in a class and can cause calls to unintended methods
BINGO!! Someone finally said it. Extension methods should come with a warning label. If you search the blogosphere, you'll see developers talking about how GREAT extension methods are and how they are going to add these great "extensions" that they always wanted to the classes that came with the class library. Imagine if I'm a newbie C# programmer and I want to perform a lot of strings to base64 encoded strings. I could create a static method and call that often, I could create a new class that has an implicit string operator that will perform the conversion or I could simply extend the string class? Which do you think I'd choose?
Sunny Ahuwanya "The beauty of the desert is that it hides a well somewhere" -- Antoine de Saint Exupéry
Sunny Ahuwanya wrote:
Which do you think I'd choose?
If you're a newbie programmer, then it doesn't matter - it'll suck. If you're just new to C#, then you'll want to play around with the tools, and it'll probably still suck. Once you've become comfortable and competent with both the language and C# in general, then you'll make a good choice given the requirements and constraints that apply. It might well be an extension method...
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You're right. These facts that you've laid out totally contradict the wild ramblings that I pulled off the back of cornflakes packets.