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Readable code, taken too far (too Swift)?

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  • raddevusR raddevus

    I'm learning Swift. It's an interesting new(er) language that has some interesting new features. Functions Have External Param Names One of those features is the naming of external function params. Background Most of us are accustomed to named (internal) params. This is analogous to what we have in C# like the following:

    int Add(int addend1, int addend2){
    return addend1 + addend2;
    }

    Of course we call it like:

    Add(2,3);

    Those internal params are the names we use inside the function body. That all makes sense. What About Swift? But in Swift you can also name the external params. Actually, you have to name them in your function definition unless you use an underscore to tell the compiler you're not using an external name. Here's the same function defined in Swift:

    func Add(_ addend1: Int, _ addend2: Int) -> Int{
    return addend1 + addend2;
    }

    You can call that method like :

    Add(2,3)

    Magical Underscore However, if we do not supply the underscore, then we have to give the external param a name too, like the following:

    func Add(a1 addend1: Int, a2 addend2: Int) -> Int{
    return addend1 + addend2;
    }

    So now you have to call the Add function like the following (or it will fail to compile):

    Add(a1:2, a2:3)

    All That Culminates In This The very good book I'm reading to learn Swift[^] has an example like the following:

    func changeName(of d:Dog, to newName:String) {
    d.name = newName
    }

    What changeName Does The changeName function takes a Dog class and changes it's name property to the value that is sent in the 2nd param (String). The external variable for the first param (of type Dog) is of and the internal name of that same param is d. The external name of the 2nd param (

    M Offline
    M Offline
    Marc Clifton
    wrote on last edited by
    #5

    Gross. So it is foisted onto the development team to making the decision as to which pattern to consistently use: _ so the syntax is changeName(d, "Rover") or to use named external parameters so the syntax is changeName(of:d, to:"Rover"). That is, if it's even a conscious decision. But of course, the next team / outsource group / other library may use the opposite pattern, so your Swift code will be a smattering of the two, and it seems like the only way to tell which one you need to use is by inspecting the function declaration? Because I seriously doubt whatever editor you use has sophisticated intellisense to help you, or am I wrong in this? So, what is the benefit of named external parameters? Merely the fact that you can also, if you're Hungarian or like RPN, write changeName(to:"Rover", of:d) ??? Is there any concept of optional parameters that have default values if not set? And even worse, can you mix the two, so you could write changeName(d, to:"Rover") ?

    Latest Article - A Concise Overview of Threads Learning to code with python is like learning to swim with those little arm floaties. It gives you undeserved confidence and will eventually drown you. - DangerBunny Artificial intelligence is the only remedy for natural stupidity. - CDP1802

    raddevusR 1 Reply Last reply
    0
    • M Marc Clifton

      Gross. So it is foisted onto the development team to making the decision as to which pattern to consistently use: _ so the syntax is changeName(d, "Rover") or to use named external parameters so the syntax is changeName(of:d, to:"Rover"). That is, if it's even a conscious decision. But of course, the next team / outsource group / other library may use the opposite pattern, so your Swift code will be a smattering of the two, and it seems like the only way to tell which one you need to use is by inspecting the function declaration? Because I seriously doubt whatever editor you use has sophisticated intellisense to help you, or am I wrong in this? So, what is the benefit of named external parameters? Merely the fact that you can also, if you're Hungarian or like RPN, write changeName(to:"Rover", of:d) ??? Is there any concept of optional parameters that have default values if not set? And even worse, can you mix the two, so you could write changeName(d, to:"Rover") ?

      Latest Article - A Concise Overview of Threads Learning to code with python is like learning to swim with those little arm floaties. It gives you undeserved confidence and will eventually drown you. - DangerBunny Artificial intelligence is the only remedy for natural stupidity. - CDP1802

      raddevusR Offline
      raddevusR Offline
      raddevus
      wrote on last edited by
      #6

      Yes, you'd have to decide at the outset if you were really going to follow that type of pattern and it could get very mixed up. Also, XCode does seem to help with a Intellisense type of functionality.

      Marc Clifton wrote:

      And even worse, can you mix the two,

      And, yes, you can definitely mix the two. The creator of the original function can use the _ to indicate the external name is not required and can use it on 0 or more params. I can see that the language creators were trying to allow developers to convey more meaning but not sure external names really help. It feels like what has recently been done with fluent interfaces[^]

      mock.expects(once()).method("m").with( or(stringContains("hello"), stringContains("howdy")) );

      The attempt to make it read like natural language. I think it works well with unit testing frameworks, but not sure about all code.

      1 Reply Last reply
      0
      • raddevusR raddevus

        I'm learning Swift. It's an interesting new(er) language that has some interesting new features. Functions Have External Param Names One of those features is the naming of external function params. Background Most of us are accustomed to named (internal) params. This is analogous to what we have in C# like the following:

        int Add(int addend1, int addend2){
        return addend1 + addend2;
        }

        Of course we call it like:

        Add(2,3);

        Those internal params are the names we use inside the function body. That all makes sense. What About Swift? But in Swift you can also name the external params. Actually, you have to name them in your function definition unless you use an underscore to tell the compiler you're not using an external name. Here's the same function defined in Swift:

        func Add(_ addend1: Int, _ addend2: Int) -> Int{
        return addend1 + addend2;
        }

        You can call that method like :

        Add(2,3)

        Magical Underscore However, if we do not supply the underscore, then we have to give the external param a name too, like the following:

        func Add(a1 addend1: Int, a2 addend2: Int) -> Int{
        return addend1 + addend2;
        }

        So now you have to call the Add function like the following (or it will fail to compile):

        Add(a1:2, a2:3)

        All That Culminates In This The very good book I'm reading to learn Swift[^] has an example like the following:

        func changeName(of d:Dog, to newName:String) {
        d.name = newName
        }

        What changeName Does The changeName function takes a Dog class and changes it's name property to the value that is sent in the 2nd param (String). The external variable for the first param (of type Dog) is of and the internal name of that same param is d. The external name of the 2nd param (

        J Offline
        J Offline
        jsc42
        wrote on last edited by
        #7

        I remember that Algol 60 (used in my uni. days) had a different approach. When calling a function, you could separate parameters using either ',' or ') :(' to give expressions like

        CHANGENAME(D) THE DOG CHANGES NAME TO :( NEWNAME)

        (we only had uppercase characters :( ). I didn't use that syntax very much - it was confusing because the ) looked like an end of a parameter list, not the start of an inline comment

        1 Reply Last reply
        0
        • C Chris Maunder

          I did kinda like that when I first learned it but then... I think I'm too steeped in keeping code compact. Not Ruby-esque compact, but the need to explicitly name every input variable started grating. I do prefer the C# way where naming input parameters is opt-in instead of opt-out.

          cheers Chris Maunder

          O Offline
          O Offline
          obermd
          wrote on last edited by
          #8

          I use this in VB (6, Applications, .Net) sometimes, but I'd prefer to have the option. Most of the time it simply doesn't help the readability of the calling code.

          1 Reply Last reply
          0
          • raddevusR raddevus

            I'm learning Swift. It's an interesting new(er) language that has some interesting new features. Functions Have External Param Names One of those features is the naming of external function params. Background Most of us are accustomed to named (internal) params. This is analogous to what we have in C# like the following:

            int Add(int addend1, int addend2){
            return addend1 + addend2;
            }

            Of course we call it like:

            Add(2,3);

            Those internal params are the names we use inside the function body. That all makes sense. What About Swift? But in Swift you can also name the external params. Actually, you have to name them in your function definition unless you use an underscore to tell the compiler you're not using an external name. Here's the same function defined in Swift:

            func Add(_ addend1: Int, _ addend2: Int) -> Int{
            return addend1 + addend2;
            }

            You can call that method like :

            Add(2,3)

            Magical Underscore However, if we do not supply the underscore, then we have to give the external param a name too, like the following:

            func Add(a1 addend1: Int, a2 addend2: Int) -> Int{
            return addend1 + addend2;
            }

            So now you have to call the Add function like the following (or it will fail to compile):

            Add(a1:2, a2:3)

            All That Culminates In This The very good book I'm reading to learn Swift[^] has an example like the following:

            func changeName(of d:Dog, to newName:String) {
            d.name = newName
            }

            What changeName Does The changeName function takes a Dog class and changes it's name property to the value that is sent in the 2nd param (String). The external variable for the first param (of type Dog) is of and the internal name of that same param is d. The external name of the 2nd param (

            D Offline
            D Offline
            Dan Neely
            wrote on last edited by
            #9

            Well I think we know where Osmo ended up.                                                                                          X| X| X| X| X|                         X| X| X| X| X| X|                             X| X| X| X| X| X| X| X| X|               X| X|                             X| X|               X| X| X| X| X| X| X| X| X| X| X| X|           X|                                                X|      X| X| X| X| X| X| X| X| X| X| X| X| X| X|      X|                                                     X| X| X| X| X| X| X| X| X| X| X| X| X| X| X| X| X|      X|               X|      X|                    X| X| X| X| X| X|

            1 Reply Last reply
            0
            • raddevusR raddevus

              I'm learning Swift. It's an interesting new(er) language that has some interesting new features. Functions Have External Param Names One of those features is the naming of external function params. Background Most of us are accustomed to named (internal) params. This is analogous to what we have in C# like the following:

              int Add(int addend1, int addend2){
              return addend1 + addend2;
              }

              Of course we call it like:

              Add(2,3);

              Those internal params are the names we use inside the function body. That all makes sense. What About Swift? But in Swift you can also name the external params. Actually, you have to name them in your function definition unless you use an underscore to tell the compiler you're not using an external name. Here's the same function defined in Swift:

              func Add(_ addend1: Int, _ addend2: Int) -> Int{
              return addend1 + addend2;
              }

              You can call that method like :

              Add(2,3)

              Magical Underscore However, if we do not supply the underscore, then we have to give the external param a name too, like the following:

              func Add(a1 addend1: Int, a2 addend2: Int) -> Int{
              return addend1 + addend2;
              }

              So now you have to call the Add function like the following (or it will fail to compile):

              Add(a1:2, a2:3)

              All That Culminates In This The very good book I'm reading to learn Swift[^] has an example like the following:

              func changeName(of d:Dog, to newName:String) {
              d.name = newName
              }

              What changeName Does The changeName function takes a Dog class and changes it's name property to the value that is sent in the 2nd param (String). The external variable for the first param (of type Dog) is of and the internal name of that same param is d. The external name of the 2nd param (

              A Offline
              A Offline
              ajhampson
              wrote on last edited by
              #10

              I think partly this is a holdover from Objective-C. For example, this Cocoa method call:

              UIAlertView* alert = [[UIAlertView alloc] initWithTitle:@"Hello!"
              message:@"Hello, world!"
              delegate:nil
              cancelButtonTitle:@"Close"
              otherButtonTitles:nil];

              which calls initWithTitle to create a new pop-up with a message for the user. It uses the external notation and if I remember correctly (always problematic) the notation was required on all but the first argument, where it was optional. This used to be more important when mixing Swift with Objective-C, but now most (if not all) of the various OS APIs are implemented in Swift, so it's less relevant. The exception is if you're using your own Objective-C code with Swift, or slowly converting a project over from one to the other.

              raddevusR 1 Reply Last reply
              0
              • raddevusR raddevus

                I'm learning Swift. It's an interesting new(er) language that has some interesting new features. Functions Have External Param Names One of those features is the naming of external function params. Background Most of us are accustomed to named (internal) params. This is analogous to what we have in C# like the following:

                int Add(int addend1, int addend2){
                return addend1 + addend2;
                }

                Of course we call it like:

                Add(2,3);

                Those internal params are the names we use inside the function body. That all makes sense. What About Swift? But in Swift you can also name the external params. Actually, you have to name them in your function definition unless you use an underscore to tell the compiler you're not using an external name. Here's the same function defined in Swift:

                func Add(_ addend1: Int, _ addend2: Int) -> Int{
                return addend1 + addend2;
                }

                You can call that method like :

                Add(2,3)

                Magical Underscore However, if we do not supply the underscore, then we have to give the external param a name too, like the following:

                func Add(a1 addend1: Int, a2 addend2: Int) -> Int{
                return addend1 + addend2;
                }

                So now you have to call the Add function like the following (or it will fail to compile):

                Add(a1:2, a2:3)

                All That Culminates In This The very good book I'm reading to learn Swift[^] has an example like the following:

                func changeName(of d:Dog, to newName:String) {
                d.name = newName
                }

                What changeName Does The changeName function takes a Dog class and changes it's name property to the value that is sent in the 2nd param (String). The external variable for the first param (of type Dog) is of and the internal name of that same param is d. The external name of the 2nd param (

                L Offline
                L Offline
                Lost User
                wrote on last edited by
                #11

                What if it's a cat? (Using C#, interfaces and "named parms")

                Cat cat = new Cat(){ Name = "Whiskers" };

                ChangeName( of: cat, to: "Fluffy" );

                // OR

                ChangeName( to: "Fluffy", of: cat );

                public STATIC void ChangeName(IRenameable of, string to) {
                of.Name = to;
                }

                public interface IRenameable {
                string Name {get;set;}
                }

                public class Cat: IRenameable {
                public string Name {get;set;}
                }

                "(I) am amazed to see myself here rather than there ... now rather than then". ― Blaise Pascal

                raddevusR 1 Reply Last reply
                0
                • L Lost User

                  What if it's a cat? (Using C#, interfaces and "named parms")

                  Cat cat = new Cat(){ Name = "Whiskers" };

                  ChangeName( of: cat, to: "Fluffy" );

                  // OR

                  ChangeName( to: "Fluffy", of: cat );

                  public STATIC void ChangeName(IRenameable of, string to) {
                  of.Name = to;
                  }

                  public interface IRenameable {
                  string Name {get;set;}
                  }

                  public class Cat: IRenameable {
                  public string Name {get;set;}
                  }

                  "(I) am amazed to see myself here rather than there ... now rather than then". ― Blaise Pascal

                  raddevusR Offline
                  raddevusR Offline
                  raddevus
                  wrote on last edited by
                  #12

                  Nice example. Do you prefer code in that style?

                  1 Reply Last reply
                  0
                  • A ajhampson

                    I think partly this is a holdover from Objective-C. For example, this Cocoa method call:

                    UIAlertView* alert = [[UIAlertView alloc] initWithTitle:@"Hello!"
                    message:@"Hello, world!"
                    delegate:nil
                    cancelButtonTitle:@"Close"
                    otherButtonTitles:nil];

                    which calls initWithTitle to create a new pop-up with a message for the user. It uses the external notation and if I remember correctly (always problematic) the notation was required on all but the first argument, where it was optional. This used to be more important when mixing Swift with Objective-C, but now most (if not all) of the various OS APIs are implemented in Swift, so it's less relevant. The exception is if you're using your own Objective-C code with Swift, or slowly converting a project over from one to the other.

                    raddevusR Offline
                    raddevusR Offline
                    raddevus
                    wrote on last edited by
                    #13

                    Interesting, thanks for explaining by connecting it back to Objective-C. :thumbsup:

                    1 Reply Last reply
                    0
                    • raddevusR raddevus

                      I'm learning Swift. It's an interesting new(er) language that has some interesting new features. Functions Have External Param Names One of those features is the naming of external function params. Background Most of us are accustomed to named (internal) params. This is analogous to what we have in C# like the following:

                      int Add(int addend1, int addend2){
                      return addend1 + addend2;
                      }

                      Of course we call it like:

                      Add(2,3);

                      Those internal params are the names we use inside the function body. That all makes sense. What About Swift? But in Swift you can also name the external params. Actually, you have to name them in your function definition unless you use an underscore to tell the compiler you're not using an external name. Here's the same function defined in Swift:

                      func Add(_ addend1: Int, _ addend2: Int) -> Int{
                      return addend1 + addend2;
                      }

                      You can call that method like :

                      Add(2,3)

                      Magical Underscore However, if we do not supply the underscore, then we have to give the external param a name too, like the following:

                      func Add(a1 addend1: Int, a2 addend2: Int) -> Int{
                      return addend1 + addend2;
                      }

                      So now you have to call the Add function like the following (or it will fail to compile):

                      Add(a1:2, a2:3)

                      All That Culminates In This The very good book I'm reading to learn Swift[^] has an example like the following:

                      func changeName(of d:Dog, to newName:String) {
                      d.name = newName
                      }

                      What changeName Does The changeName function takes a Dog class and changes it's name property to the value that is sent in the 2nd param (String). The external variable for the first param (of type Dog) is of and the internal name of that same param is d. The external name of the 2nd param (

                      J Offline
                      J Offline
                      Jon McKee
                      wrote on last edited by
                      #14

                      Wow. I've recently learned Prolog (though I still have a much greater fondness for TLA+[^]) so I appreciate the _ "forget-about-it" convention but wow, requiring named parameters in absence of "anonymous" ones? FeelsBadMan :suss: Just use F#, C#, or others depending on your needs. Apple doesn't do anything well including their phone which is based mostly on advertising.

                      raddevusR 1 Reply Last reply
                      0
                      • J Jon McKee

                        Wow. I've recently learned Prolog (though I still have a much greater fondness for TLA+[^]) so I appreciate the _ "forget-about-it" convention but wow, requiring named parameters in absence of "anonymous" ones? FeelsBadMan :suss: Just use F#, C#, or others depending on your needs. Apple doesn't do anything well including their phone which is based mostly on advertising.

                        raddevusR Offline
                        raddevusR Offline
                        raddevus
                        wrote on last edited by
                        #15

                        Jon McKee wrote:

                        requiring named parameters in absence of "anonymous" ones? FeelsBadMan

                        :thumbsup: I agree.

                        1 Reply Last reply
                        0
                        • raddevusR raddevus

                          I'm learning Swift. It's an interesting new(er) language that has some interesting new features. Functions Have External Param Names One of those features is the naming of external function params. Background Most of us are accustomed to named (internal) params. This is analogous to what we have in C# like the following:

                          int Add(int addend1, int addend2){
                          return addend1 + addend2;
                          }

                          Of course we call it like:

                          Add(2,3);

                          Those internal params are the names we use inside the function body. That all makes sense. What About Swift? But in Swift you can also name the external params. Actually, you have to name them in your function definition unless you use an underscore to tell the compiler you're not using an external name. Here's the same function defined in Swift:

                          func Add(_ addend1: Int, _ addend2: Int) -> Int{
                          return addend1 + addend2;
                          }

                          You can call that method like :

                          Add(2,3)

                          Magical Underscore However, if we do not supply the underscore, then we have to give the external param a name too, like the following:

                          func Add(a1 addend1: Int, a2 addend2: Int) -> Int{
                          return addend1 + addend2;
                          }

                          So now you have to call the Add function like the following (or it will fail to compile):

                          Add(a1:2, a2:3)

                          All That Culminates In This The very good book I'm reading to learn Swift[^] has an example like the following:

                          func changeName(of d:Dog, to newName:String) {
                          d.name = newName
                          }

                          What changeName Does The changeName function takes a Dog class and changes it's name property to the value that is sent in the 2nd param (String). The external variable for the first param (of type Dog) is of and the internal name of that same param is d. The external name of the 2nd param (

                          L Offline
                          L Offline
                          Lutoslaw
                          wrote on last edited by
                          #16

                          IMHO it's requiring coders do what's basically IDE's job. See the "Parameter name hints" in this Idea manpage: View code reference info - Help | IntelliJ IDEA[^]

                          A 1 Reply Last reply
                          0
                          • L Lutoslaw

                            IMHO it's requiring coders do what's basically IDE's job. See the "Parameter name hints" in this Idea manpage: View code reference info - Help | IntelliJ IDEA[^]

                            A Offline
                            A Offline
                            Andre Pereira
                            wrote on last edited by
                            #17

                            Quote:

                            IMHO it's requiring coders do what's basically IDE's job.

                            Ding ding, we have a winner. Did not expect this from Apple.

                            L 1 Reply Last reply
                            0
                            • A Andre Pereira

                              Quote:

                              IMHO it's requiring coders do what's basically IDE's job.

                              Ding ding, we have a winner. Did not expect this from Apple.

                              L Offline
                              L Offline
                              Lutoslaw
                              wrote on last edited by
                              #18

                              Why Apple? Idea is Jet Brains'.

                              A 1 Reply Last reply
                              0
                              • L Lutoslaw

                                Why Apple? Idea is Jet Brains'.

                                A Offline
                                A Offline
                                Andre Pereira
                                wrote on last edited by
                                #19

                                The topic is on Swift language, not a particular IDE. And for the record, programmers at Apple are old-school idiots who think syntactic sparseness is compatible with security code worked by other 5000 people.

                                L R 2 Replies Last reply
                                0
                                • raddevusR raddevus

                                  I'm learning Swift. It's an interesting new(er) language that has some interesting new features. Functions Have External Param Names One of those features is the naming of external function params. Background Most of us are accustomed to named (internal) params. This is analogous to what we have in C# like the following:

                                  int Add(int addend1, int addend2){
                                  return addend1 + addend2;
                                  }

                                  Of course we call it like:

                                  Add(2,3);

                                  Those internal params are the names we use inside the function body. That all makes sense. What About Swift? But in Swift you can also name the external params. Actually, you have to name them in your function definition unless you use an underscore to tell the compiler you're not using an external name. Here's the same function defined in Swift:

                                  func Add(_ addend1: Int, _ addend2: Int) -> Int{
                                  return addend1 + addend2;
                                  }

                                  You can call that method like :

                                  Add(2,3)

                                  Magical Underscore However, if we do not supply the underscore, then we have to give the external param a name too, like the following:

                                  func Add(a1 addend1: Int, a2 addend2: Int) -> Int{
                                  return addend1 + addend2;
                                  }

                                  So now you have to call the Add function like the following (or it will fail to compile):

                                  Add(a1:2, a2:3)

                                  All That Culminates In This The very good book I'm reading to learn Swift[^] has an example like the following:

                                  func changeName(of d:Dog, to newName:String) {
                                  d.name = newName
                                  }

                                  What changeName Does The changeName function takes a Dog class and changes it's name property to the value that is sent in the 2nd param (String). The external variable for the first param (of type Dog) is of and the internal name of that same param is d. The external name of the 2nd param (

                                  R Offline
                                  R Offline
                                  Rob Grainger
                                  wrote on last edited by
                                  #20

                                  Smalltalk had similar readability, achieved differently. In this case, an object kennel may define a method changeNameOf:To: would be invoked as follows:

                                  kennel changeNameOf: d To: 'Fido'.

                                  "If you don't fail at least 90 percent of the time, you're not aiming high enough." Alan Kay.

                                  raddevusR 1 Reply Last reply
                                  0
                                  • R Rob Grainger

                                    Smalltalk had similar readability, achieved differently. In this case, an object kennel may define a method changeNameOf:To: would be invoked as follows:

                                    kennel changeNameOf: d To: 'Fido'.

                                    "If you don't fail at least 90 percent of the time, you're not aiming high enough." Alan Kay.

                                    raddevusR Offline
                                    raddevusR Offline
                                    raddevus
                                    wrote on last edited by
                                    #21

                                    Rob Grainger wrote:

                                    Smalltalk had similar readability, achieved differently

                                    Interesting. So what you're saying is that Swift is trying to copy syntax that is used by a 46 year old language. :laugh: Just kidding.

                                    R 1 Reply Last reply
                                    0
                                    • A Andre Pereira

                                      The topic is on Swift language, not a particular IDE. And for the record, programmers at Apple are old-school idiots who think syntactic sparseness is compatible with security code worked by other 5000 people.

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                                      Lutoslaw
                                      wrote on last edited by
                                      #22

                                      My point was that language designers spent time to add a future which enforces some stupid rule on developers, instead spending that time implementing an IDE plugin which does the job (likely faster and better than developers anyway). Because everybody uses IDE nowadays, right? Uhm... wait. And for the recored, no-single-liners and no-assigment-in-comparison policies suddenly started to make sense... idiots.

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                                      • raddevusR raddevus

                                        I'm learning Swift. It's an interesting new(er) language that has some interesting new features. Functions Have External Param Names One of those features is the naming of external function params. Background Most of us are accustomed to named (internal) params. This is analogous to what we have in C# like the following:

                                        int Add(int addend1, int addend2){
                                        return addend1 + addend2;
                                        }

                                        Of course we call it like:

                                        Add(2,3);

                                        Those internal params are the names we use inside the function body. That all makes sense. What About Swift? But in Swift you can also name the external params. Actually, you have to name them in your function definition unless you use an underscore to tell the compiler you're not using an external name. Here's the same function defined in Swift:

                                        func Add(_ addend1: Int, _ addend2: Int) -> Int{
                                        return addend1 + addend2;
                                        }

                                        You can call that method like :

                                        Add(2,3)

                                        Magical Underscore However, if we do not supply the underscore, then we have to give the external param a name too, like the following:

                                        func Add(a1 addend1: Int, a2 addend2: Int) -> Int{
                                        return addend1 + addend2;
                                        }

                                        So now you have to call the Add function like the following (or it will fail to compile):

                                        Add(a1:2, a2:3)

                                        All That Culminates In This The very good book I'm reading to learn Swift[^] has an example like the following:

                                        func changeName(of d:Dog, to newName:String) {
                                        d.name = newName
                                        }

                                        What changeName Does The changeName function takes a Dog class and changes it's name property to the value that is sent in the 2nd param (String). The external variable for the first param (of type Dog) is of and the internal name of that same param is d. The external name of the 2nd param (

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                                        KarstenK
                                        wrote on last edited by
                                        #23

                                        I'll have to learn and use Swift. This year ... :~

                                        Press F1 for help or google it. Greetings from Germany

                                        raddevusR 1 Reply Last reply
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                                        • K KarstenK

                                          I'll have to learn and use Swift. This year ... :~

                                          Press F1 for help or google it. Greetings from Germany

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                                          raddevus
                                          wrote on last edited by
                                          #24

                                          Good luck. I started writing some of it up here at CP : iOS 12 Programming Fundamentals With Swift: Intro & Chpt1[^] I find that learning Xcode (IDE) is a barrier too. I'm definitely accustomed to VStudio and Android Studio. The odd way that you add code when a button is clicked (see article) just doesn't feel natural to me.

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