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  • P PIEBALDconsult

    No.

    W Offline
    W Offline
    wout de zeeuw
    wrote on last edited by
    #32

    Yes.

    Wout

    C 1 Reply Last reply
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    • M Marc Clifton

      So, there's been a lot of posts about whether var (C# thingy, for those non-C# folks) is good, bad, or just ugly. Well, I can deal with: var foo = new List(); as an example, because it's obvious what foo is. What I really hate is something like this: var foo = factory.CreateAFoo() That's where I despise seeing a "var"! Marc

      Will work for food. Interacx

      I'm not overthinking the problem, I just felt like I needed a small, unimportant, uninteresting rant! - Martin Hart Turner

      N Offline
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      Nish Nishant
      wrote on last edited by
      #33

      Marc Clifton wrote:

      var foo = factory.CreateAFoo() That's where I despise seeing a "var"!

      Well if both the variable and the factory method are named properly, I don't think there'd be any confusion here. If they are not, then using var would be the least of the issues here.

      Regards, Nish


      Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
      My latest book : C++/CLI in Action / Amazon.com link

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      • W wout de zeeuw

        Huh? Isn't the point of var and anonymous types less typing? Otherwise one would type out all these types explicitly. Other than amount of typing I see no advantage in var.

        Wout

        T Offline
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        TheGreatAndPowerfulOz
        wrote on last edited by
        #34

        no, the point was more to be able to have anonymous types and also in foreach and other like constructs where the type info can be combersomely unwieldy to have something more readable and understandable.

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        • I Ian Shlasko

          public class MyRidiculousClass : IEnumerable<Dictionary<int, Dictionary<int, List<int>>>>
          {
          }

          Now CreateAFoo() can return something legible :)

          Proud to have finally moved to the A-Ark. Which one are you in? Developer, Author (Guardians of Xen)

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          TheGreatAndPowerfulOz
          wrote on last edited by
          #35

          yes, true, but you're not always using your own "reasonable" code...

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          • I Ian Shlasko

            public class MyRidiculousClass : IEnumerable<Dictionary<int, Dictionary<int, List<int>>>>
            {
            }

            Now CreateAFoo() can return something legible :)

            Proud to have finally moved to the A-Ark. Which one are you in? Developer, Author (Guardians of Xen)

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            AspDotNetDev
            wrote on last edited by
            #36

            Then you lose any constructors the base type might have had. Although it's annoying you have to fully qualify the namespaces, you could also do this:

            using TooLong = System.Collections.Generic.IEnumerable<System.Collections.Generic.Dictionary<int, System.Collections.Generic.Dictionary<int, System.Collections.Generic.List<int>>>>;

            Visual Studio is an excellent GUIIDE.

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            • M Marc Clifton

              Nemanja Trifunovic wrote:

              Meh, in your example foo is either Foo or IFoo.

              Agreed. The example was bad, but you know what I meant. :)

              Nemanja Trifunovic wrote:

              why on earth C# (or Java) need keyword new in the first place? It is completely redundant.

              Because it gives everyone a warm fuzzy feeling that something important is happening. Just be glad we don't have to use the "Let" keyword (though, in some functional languages, it's baaaaack!) Marc

              Will work for food. Interacx

              I'm not overthinking the problem, I just felt like I needed a small, unimportant, uninteresting rant! - Martin Hart Turner

              R Offline
              R Offline
              Roger Wright
              wrote on last edited by
              #37

              But what if you want to reuse an object for something completely different. Can you declare var Foo2 = old FooObject; ?

              "A Journey of a Thousand Rest Stops Begins with a Single Movement"

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              • I Ian Shlasko

                I kind of like the "new" keyword, but technically it shouldn't be needed, unless I'm missing something. Just playing devil's advocate here...

                With: List<string> myList = new List<string>();
                Without: List<string> myList = List<string>();

                The parentheses would be enough to indicate that you're calling a constructor... I do think, though, that the "new" keyword keeps things clearer. There could be issues with functions named the same as classes, but that could technically be resolved with absolute references.

                Proud to have finally moved to the A-Ark. Which one are you in? Developer, Author (Guardians of Xen)

                P Offline
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                PIEBALDconsult
                wrote on last edited by
                #38

                List<string> myList = List<string>.ctor() ; Much more orthogonal. :-D

                1 Reply Last reply
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                • M Marc Clifton

                  So, there's been a lot of posts about whether var (C# thingy, for those non-C# folks) is good, bad, or just ugly. Well, I can deal with: var foo = new List(); as an example, because it's obvious what foo is. What I really hate is something like this: var foo = factory.CreateAFoo() That's where I despise seeing a "var"! Marc

                  Will work for food. Interacx

                  I'm not overthinking the problem, I just felt like I needed a small, unimportant, uninteresting rant! - Martin Hart Turner

                  P Offline
                  P Offline
                  Plamen Dragiyski
                  wrote on last edited by
                  #39

                  //C/C++:
                  void *foo = (void*)new Foo();
                  //What is foo?
                  foo = (void*)myClass.createFoo();
                  //And now?
                  foo = (void*)&any_type_variable;
                  //now?
                  foo = (void*)&foo;
                  //O.o

                  Seems nice to me :P

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                  • R Roger Wright

                    But what if you want to reuse an object for something completely different. Can you declare var Foo2 = old FooObject; ?

                    "A Journey of a Thousand Rest Stops Begins with a Single Movement"

                    J Offline
                    J Offline
                    Jorgen Sigvardsson
                    wrote on last edited by
                    #40

                    let var Foo2 = old FooObject; of course... (Seriously, no. The compiler substitutes the var keyword with the real type at compile time. It's not a dynamic type.)

                    -- Kein Mitleid Für Die Mehrheit

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                    • M Marc Clifton

                      So, there's been a lot of posts about whether var (C# thingy, for those non-C# folks) is good, bad, or just ugly. Well, I can deal with: var foo = new List(); as an example, because it's obvious what foo is. What I really hate is something like this: var foo = factory.CreateAFoo() That's where I despise seeing a "var"! Marc

                      Will work for food. Interacx

                      I'm not overthinking the problem, I just felt like I needed a small, unimportant, uninteresting rant! - Martin Hart Turner

                      D Offline
                      D Offline
                      dazfuller
                      wrote on last edited by
                      #41

                      I hate it because you can't tell at a glance what the type is, okay so its alright for anonymous types where you don't know but otherwise it's just a train-wreck. I still think that the following is cleaner, easier to read and less prone to human error: List foo = new List(); and IFoo foo = factory.CreateAFoo()

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                      • C Chris Losinger

                        Marc Clifton wrote:

                        var foo = factory.CreateAFoo()

                        into every language a little void * must fall.

                        image processing toolkits | batch image processing

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                        Adar Wesley
                        wrote on last edited by
                        #42

                        Chris Losinger wrote:

                        Marc Clifton wrote: var foo = factory.CreateAFoo() into every language a little void * must fall.

                        In the above case, foo is NOT void *. It is a strongly typed variable of the type factory.CreateAFoo() returns. For instance:

                        var str = "This is a string variable";
                        str = 5; // <-- Compile error

                        Incidently, I love to use var. During development you change the type of a variable by changing the initialization code and not have to go also and fix the variable declared type. So if I have in my code the above mentioned function declared as so:

                        internal Foo CreateAFoo()
                        {
                        // create and return a Foo
                        }

                        And somewhere else:

                        var foo = factory.CreateAFoo()

                        Then, during the developement process, I think: "let's change my work from Foo to IFoo to introduce different implementations". All I have to do is change the signature of CreateAFoo() to:

                        internal IFoo CreateAFoo()
                        {
                        // create and return a Foo
                        }

                        That's it, all done. Don't need to wory about changing all the variables all over the code that hold a Foo reference. They automatically become IFoo references. --- Adar Wesley

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                        • M Michael Dunn

                          It still bugs me that you can't write "new List" in C#, you have to write "new List()" But maybe I'm just a crusty old C++ guy. ;P

                          --Mike-- Dunder-Mifflin, this is Pam

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                          Wenff
                          wrote on last edited by
                          #43

                          Talk about lazy! Is t really that hard type ()? ;P

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                          • R Roger Wright

                            But what if you want to reuse an object for something completely different. Can you declare var Foo2 = old FooObject; ?

                            "A Journey of a Thousand Rest Stops Begins with a Single Movement"

                            S Offline
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                            smcnulty2000
                            wrote on last edited by
                            #44

                            Roger Wright wrote:

                            var Foo2 = old FooObject;

                            There's no foo like an old foo. So, clearly not.

                            _____________________________ There is no I in team. But there is meat in there.

                            R 1 Reply Last reply
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                            • P PIEBALDconsult

                              var wasn't created to reduce keystrokes, and should not be used as such. Developers should strive to type more keystrokes, not fewer.

                              K Offline
                              K Offline
                              K v S
                              wrote on last edited by
                              #45

                              :laugh: try COBOL

                              1 Reply Last reply
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                              • T TheGreatAndPowerfulOz

                                no, the point was more to be able to have anonymous types and also in foreach and other like constructs where the type info can be combersomely unwieldy to have something more readable and understandable.

                                W Offline
                                W Offline
                                wout de zeeuw
                                wrote on last edited by
                                #46

                                It only saves some typing, other than that it doesn't offer anything functional. I can make my own custom classes to contain my query/filter results, which will always be more readable than a non-descriptive var.

                                Wout

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                                • J Judah Gabriel Himango

                                  My opinion: I'm kind of liking var. Everywhere. While I might not be able to tell the type at only a quick glance, as you say in your post, it makes the code much cleaner and elegant, IMO, as the variable declarations all stand out as a single group.

                                  Religiously blogging on the intarwebs since the early 21st century: Kineti L'Tziyon Judah Himango

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                                  codemunkeh
                                  wrote on last edited by
                                  #47

                                  Why not just make all your own custom types 7 characters long; and build wrappers around the base classes to make them 7 characters long too?

                                  QString bork = string.Empty
                                  QQFloat FHeight = 12.0F

                                  Really, what I normally do is group the declarations at the top of a class inside a #region Declarations then shrink it when not needed.


                                  Ninja (the Nerd)
                                  Confused? You will be...

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                                  • W wout de zeeuw

                                    Yes.

                                    Wout

                                    C Offline
                                    C Offline
                                    codemunkeh
                                    wrote on last edited by
                                    #48

                                    UnstableClassInDevelopment.UnStableType.UnderlyingValue obj = new UnstableClassInDevelopment.UnStableType.UnderlyingValue();

                                    Now, if that underlying value changes type; everything breaks. With var, you don't have to do any search/replace and it works with any reasonable change. Yes, stupid example but I don't even use the thing.


                                    Ninja (the Nerd)
                                    Confused? You will be...

                                    W 1 Reply Last reply
                                    0
                                    • C codemunkeh

                                      UnstableClassInDevelopment.UnStableType.UnderlyingValue obj = new UnstableClassInDevelopment.UnStableType.UnderlyingValue();

                                      Now, if that underlying value changes type; everything breaks. With var, you don't have to do any search/replace and it works with any reasonable change. Yes, stupid example but I don't even use the thing.


                                      Ninja (the Nerd)
                                      Confused? You will be...

                                      W Offline
                                      W Offline
                                      wout de zeeuw
                                      wrote on last edited by
                                      #49

                                      You can just rename the type with VS refactoring couldn't you? And if some third party owns that code and changes it, I would like everything to break, so I can see what the change was exactly. Silently accepting changes is very dangerous.

                                      Wout

                                      P 1 Reply Last reply
                                      0
                                      • I Ian Shlasko

                                        I kind of like the "new" keyword, but technically it shouldn't be needed, unless I'm missing something. Just playing devil's advocate here...

                                        With: List<string> myList = new List<string>();
                                        Without: List<string> myList = List<string>();

                                        The parentheses would be enough to indicate that you're calling a constructor... I do think, though, that the "new" keyword keeps things clearer. There could be issues with functions named the same as classes, but that could technically be resolved with absolute references.

                                        Proud to have finally moved to the A-Ark. Which one are you in? Developer, Author (Guardians of Xen)

                                        J Offline
                                        J Offline
                                        James Curran
                                        wrote on last edited by
                                        #50

                                        var foo = new MyFoo(); //clearly creates a new MyFoo. var foo = MyFoo(); //create a new MyFoo or call local method MyFoo()? var foo = MyFoo; //create a new MyFoo or assign local field MyFoo?

                                        Truth, James

                                        1 Reply Last reply
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                                        • S smcnulty2000

                                          Roger Wright wrote:

                                          var Foo2 = old FooObject;

                                          There's no foo like an old foo. So, clearly not.

                                          _____________________________ There is no I in team. But there is meat in there.

                                          R Offline
                                          R Offline
                                          Richard Jones
                                          wrote on last edited by
                                          #51

                                          I pity the foo! - Mr <T>

                                          "The activity of 'debugging', or removing bugs from a program, ends when people get tired of doing it, not when the bugs are removed." - "Datamation", January 15, 1984

                                          M 1 Reply Last reply
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