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  3. You'll be glad to know! [modified]

You'll be glad to know! [modified]

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  • S Super Lloyd

    Ok, maybe I should say what I did, so maybe an anti-goto purist can give me tips on how to write goto-less nice code in such circumstances... (or become less anti goto) so here we go, that's what I wrote (veil your eyes, code in the lounge!)

    for(...)
    {
    avar = calculation()
    if(avar == someValue)
    goto doStuff;
    avar2 = someOtherCalculation();
    if(avar2 == someValue2)
    goto doStuff;
    continue;
    doStuff:;
    localVar.UpdateNicely();
    }

    A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

    L Offline
    L Offline
    Luc Pattyn
    wrote on last edited by
    #12

    You really should read part 2 of your Language Reference Manual, in particular the chapters on logical operators and short-circuitry.

    for (...) {
    if (calculation()==someValue || someOtherCalculation()==someValue2) localVar.UpdateNicely();
    }

    Readability is the key concern here. :)

    Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

    Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

    D S A 4 Replies Last reply
    0
    • A AspDotNetDev

      Delete this post before everybody sees and you are shamed!

      [Forum Guidelines]

      D Offline
      D Offline
      Dalek Dave
      wrote on last edited by
      #13

      Early 80's programming is in my blood! I just can't let go of them goto statements :)

      ------------------------------------ I will never again mention that I was the poster of the One Millionth Lounge Post, nor that it was complete drivel. Dalek Dave CCC League Table Link CCC Link[^]

      1 Reply Last reply
      0
      • L Luc Pattyn

        You really should read part 2 of your Language Reference Manual, in particular the chapters on logical operators and short-circuitry.

        for (...) {
        if (calculation()==someValue || someOtherCalculation()==someValue2) localVar.UpdateNicely();
        }

        Readability is the key concern here. :)

        Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

        Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

        D Offline
        D Offline
        Dalek Dave
        wrote on last edited by
        #14

        That's actually a nice bit of code. I have much to learm :sigh:

        ------------------------------------ I will never again mention that I was the poster of the One Millionth Lounge Post, nor that it was complete drivel. Dalek Dave CCC League Table Link CCC Link[^]

        L 1 Reply Last reply
        0
        • S Super Lloyd

          Ok, maybe I should say what I did, so maybe an anti-goto purist can give me tips on how to write goto-less nice code in such circumstances... (or become less anti goto) so here we go, that's what I wrote (veil your eyes, code in the lounge!)

          for(...)
          {
          avar = calculation()
          if(avar == someValue)
          goto doStuff;
          avar2 = someOtherCalculation();
          if(avar2 == someValue2)
          goto doStuff;
          continue;
          doStuff:;
          localVar.UpdateNicely();
          }

          A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

          P Offline
          P Offline
          Peter_in_2780
          wrote on last edited by
          #15

          How about

          for(...)
          {
          avar = calculation()
          if(avar != someValue)
          {
          avar2 = someOtherCalculation();
          if(avar2 != someValue2)
          continue;
          }
          localVar.UpdateNicely();
          }

          The point is basically that

          if (something)
          goto somewhere
          more_stuff;
          somewhere:

          is equivalent to

          if (!something)
          more_stuff;

          and you've just got two of them nested. Cheers from one who thinks coding standards are generally a good thing but do not represent ultimate authority. Peter

          Software rusts. Simon Stephenson, ca 1994.

          S 1 Reply Last reply
          0
          • L Luc Pattyn

            You really should read part 2 of your Language Reference Manual, in particular the chapters on logical operators and short-circuitry.

            for (...) {
            if (calculation()==someValue || someOtherCalculation()==someValue2) localVar.UpdateNicely();
            }

            Readability is the key concern here. :)

            Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

            Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

            S Offline
            S Offline
            Super Lloyd
            wrote on last edited by
            #16

            well, I wanted to use some simple pseudo code, but the statement "var1 = calculation()" is really a multi inner variable multiline statement with a more complex statement. I guess I can replace it with a private static variable with heaps of ref variable just or the sake of writing such statement as you sugest, but I won't!

            A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

            L 1 Reply Last reply
            0
            • S Super Lloyd

              I thought about it and... despite my initial inflamatory intention I'm thinking we could both gain by showing you what I did, who knows one of 2 thing might even happen!! 1. maybe you'll think this is a good goto! 2. maybe you'll give me good work around so, here you go (veil your eyes, code in the lounge) please remove the goto in the nice fashion or hold your peace forever!

              for(...)
              {
              avar = calculation()
              if(avar == someValue)
              goto doStuff;
              avar2 = someOtherCalculation();
              if(avar2 == someValue2)
              goto doStuff;
              continue;
              doStuff:;
              localVar.UpdateNicely();
              }

              A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

              A Offline
              A Offline
              AspDotNetDev
              wrote on last edited by
              #17

              No excuse!

              for(...)
              {
              if(calc() == v || calc2() == v2)
              {
              localVar.UpdateNicely();
              }
              }

              [Forum Guidelines]

              1 Reply Last reply
              0
              • L Luc Pattyn

                You really should read part 2 of your Language Reference Manual, in particular the chapters on logical operators and short-circuitry.

                for (...) {
                if (calculation()==someValue || someOtherCalculation()==someValue2) localVar.UpdateNicely();
                }

                Readability is the key concern here. :)

                Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

                Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

                A Offline
                A Offline
                AspDotNetDev
                wrote on last edited by
                #18

                Dang, you beat me.

                [Forum Guidelines]

                L 1 Reply Last reply
                0
                • P Peter_in_2780

                  How about

                  for(...)
                  {
                  avar = calculation()
                  if(avar != someValue)
                  {
                  avar2 = someOtherCalculation();
                  if(avar2 != someValue2)
                  continue;
                  }
                  localVar.UpdateNicely();
                  }

                  The point is basically that

                  if (something)
                  goto somewhere
                  more_stuff;
                  somewhere:

                  is equivalent to

                  if (!something)
                  more_stuff;

                  and you've just got two of them nested. Cheers from one who thinks coding standards are generally a good thing but do not represent ultimate authority. Peter

                  Software rusts. Simon Stephenson, ca 1994.

                  S Offline
                  S Offline
                  Super Lloyd
                  wrote on last edited by
                  #19

                  Indeed that will do! :thumbsup: :) However.... I do prefer goto to multiple nested statement! ;P

                  A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

                  D P 2 Replies Last reply
                  0
                  • A AspDotNetDev

                    Dang, you beat me.

                    [Forum Guidelines]

                    L Offline
                    L Offline
                    Luc Pattyn
                    wrote on last edited by
                    #20

                    the advantage of a keyboard with a very short cable. :)

                    Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

                    Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

                    1 Reply Last reply
                    0
                    • S Super Lloyd

                      Indeed that will do! :thumbsup: :) However.... I do prefer goto to multiple nested statement! ;P

                      A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

                      D Offline
                      D Offline
                      Dalek Dave
                      wrote on last edited by
                      #21

                      It's neater.

                      ------------------------------------ I will never again mention that I was the poster of the One Millionth Lounge Post, nor that it was complete drivel. Dalek Dave CCC League Table Link CCC Link[^]

                      S 1 Reply Last reply
                      0
                      • L Luc Pattyn

                        You really should read part 2 of your Language Reference Manual, in particular the chapters on logical operators and short-circuitry.

                        for (...) {
                        if (calculation()==someValue || someOtherCalculation()==someValue2) localVar.UpdateNicely();
                        }

                        Readability is the key concern here. :)

                        Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

                        Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

                        S Offline
                        S Offline
                        Super Lloyd
                        wrote on last edited by
                        #22

                        there is the matter of avoiding goto, but this is no big deal, the real challenge is to do it in aesthetic and readable way! Well, I guess it's a subjective matter... But just to give you better chance, here is the real code. I think goto is the most elegant / beautiful solution. I invite you to show me the beauty of avoiding goto! (Although.. being a subjective thing... well....) Here we go:

                        for (int i = max; i >= min; i--)
                        {
                        var v1 = new Vector2D(points[i > 0 ? i - 1 : points.Count - 1], points[i]);
                        var v2 = new Vector2D(points[i], points[i < points.Count - 1 ? i + 1 : 0]);
                        if (v1.SquareNorm <= MINL || v2.SquareNorm <= MINL)
                        goto RemovePoint;
                        v1 = v1.Normalize(); // divide by zero if test above fail
                        v2 = v2.Normalize();
                        var z = v1 ^ v2;
                        if (Math.Abs(z) <= minsin && v1 * v2 < 0)
                        goto RemovePoint;
                        continue;
                        RemovePoint: ;
                        points.RemoveAt(i);
                        if (points.Count < 3)
                        return null;
                        }

                        A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

                        modified on Thursday, September 9, 2010 8:31 PM

                        A 1 Reply Last reply
                        0
                        • S Super Lloyd

                          Yesterday I wrote no less than 2 gotos in my C# code! [Edit2] This guy[^] found a satisfying refactoring! One which doesn't tax my (limited brain) memory with nested block, additional variable, additional test, increased cyclomatic complexity! (In fact the cyclomatic complexity is reduced by 1, I think) Well done! :thumbsup: :cool: :-D [EDIT] For your information the real code is below. So far no one has come up with a non goto version which can beat the goto version on any of those 4 criteria: - number of line of code (less) - number of if (less) - number of nested block (less) - number of variables (less) -- code --

                          for (int i = max; i >= min; i--)
                          {
                          var v1 = new Vector2D(points[i > 0 ? i - 1 : points.Count - 1], points[i]);
                          var v2 = new Vector2D(points[i], points[i < points.Count - 1 ? i + 1 : 0]);
                          if (v1.SquareNorm <= MINL || v2.SquareNorm <= MINL)
                          goto RemovePoint;
                          v1 = v1.Normalize(); // divide by zero if square norm is 0 (test above)
                          v2 = v2.Normalize();
                          var z = v1 ^ v2;
                          if (Math.Abs(z) <= minsin && v1 * v2 < 0)
                          goto RemovePoint;
                          continue;
                          RemovePoint: ;
                          points.RemoveAt(i);
                          if (points.Count < 3)
                          return null;
                          }

                          A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

                          modified on Friday, September 10, 2010 10:53 AM

                          P Offline
                          P Offline
                          PIEBALDconsult
                          wrote on last edited by
                          #23

                          Until I did some refactoring today I had a method with three return statements! :omg: (They were to avoid a goto to abort a nested loop.)

                          A S 2 Replies Last reply
                          0
                          • S Super Lloyd

                            Yesterday I wrote no less than 2 gotos in my C# code! [Edit2] This guy[^] found a satisfying refactoring! One which doesn't tax my (limited brain) memory with nested block, additional variable, additional test, increased cyclomatic complexity! (In fact the cyclomatic complexity is reduced by 1, I think) Well done! :thumbsup: :cool: :-D [EDIT] For your information the real code is below. So far no one has come up with a non goto version which can beat the goto version on any of those 4 criteria: - number of line of code (less) - number of if (less) - number of nested block (less) - number of variables (less) -- code --

                            for (int i = max; i >= min; i--)
                            {
                            var v1 = new Vector2D(points[i > 0 ? i - 1 : points.Count - 1], points[i]);
                            var v2 = new Vector2D(points[i], points[i < points.Count - 1 ? i + 1 : 0]);
                            if (v1.SquareNorm <= MINL || v2.SquareNorm <= MINL)
                            goto RemovePoint;
                            v1 = v1.Normalize(); // divide by zero if square norm is 0 (test above)
                            v2 = v2.Normalize();
                            var z = v1 ^ v2;
                            if (Math.Abs(z) <= minsin && v1 * v2 < 0)
                            goto RemovePoint;
                            continue;
                            RemovePoint: ;
                            points.RemoveAt(i);
                            if (points.Count < 3)
                            return null;
                            }

                            A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

                            modified on Friday, September 10, 2010 10:53 AM

                            A Offline
                            A Offline
                            AspDotNetDev
                            wrote on last edited by
                            #24

                            The only acceptable place I've found for a goto is within a switch block. After all, the "labels" are already defined.

                            [Forum Guidelines]

                            C 1 Reply Last reply
                            0
                            • S Super Lloyd

                              well, I wanted to use some simple pseudo code, but the statement "var1 = calculation()" is really a multi inner variable multiline statement with a more complex statement. I guess I can replace it with a private static variable with heaps of ref variable just or the sake of writing such statement as you sugest, but I won't!

                              A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

                              L Offline
                              L Offline
                              Luc Pattyn
                              wrote on last edited by
                              #25

                              Well, the complexity of avar1 = someCalculation(); isn't relevant, you can do it upfront anyway. The complexity of avar2 = someOtherCalculation(); is what matters. If it can't be put in the middle of the if clause, I'd use a boolean flag, like so:

                              for (...) {
                              bool updateWanted=false;
                              if (calculation()==someValue) updateWanted=true;
                              else if (someOtherCalculation()==someValue2) updateWanted=true;
                              if (updateWanted) localVar.UpdateNicely();
                              }

                              and now you can easily expand line 4 (and 3) as required. :)

                              Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

                              Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

                              modified on Thursday, September 9, 2010 8:52 PM

                              S 2 Replies Last reply
                              0
                              • P PIEBALDconsult

                                Until I did some refactoring today I had a method with three return statements! :omg: (They were to avoid a goto to abort a nested loop.)

                                A Offline
                                A Offline
                                AspDotNetDev
                                wrote on last edited by
                                #26

                                PIEBALDconsult wrote:

                                avoid a goto to abort a nested loop

                                I usually set some bool, break, then conditionally break depending on the value in the bool. Slows things down a bit, so a goto might be more acceptable in this case if speed is of significant importance and the inner loop does not have many iterations.

                                [Forum Guidelines]

                                1 Reply Last reply
                                0
                                • L Luc Pattyn

                                  Well, the complexity of avar1 = someCalculation(); isn't relevant, you can do it upfront anyway. The complexity of avar2 = someOtherCalculation(); is what matters. If it can't be put in the middle of the if clause, I'd use a boolean flag, like so:

                                  for (...) {
                                  bool updateWanted=false;
                                  if (calculation()==someValue) updateWanted=true;
                                  else if (someOtherCalculation()==someValue2) updateWanted=true;
                                  if (updateWanted) localVar.UpdateNicely();
                                  }

                                  and now you can easily expand line 4 (and 3) as required. :)

                                  Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

                                  Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

                                  modified on Thursday, September 9, 2010 8:52 PM

                                  S Offline
                                  S Offline
                                  Super Lloyd
                                  wrote on last edited by
                                  #27

                                  see the code below! it can't be done upfront, as the first if will avoid as divide by zero in the second if! just for your benefit I post the code below again! Anyway, yes it can be done, but I found my way more readable... I guess it's too subjective for debate.. but I invite you to show me the new version:

                                  for (int i = max; i >= min; i--)
                                  {
                                  var v1 = new Vector2D(points[i > 0 ? i - 1 : points.Count - 1], points[i]);
                                  var v2 = new Vector2D(points[i], points[i < points.Count - 1 ? i + 1 : 0]);
                                  if (v1.SquareNorm <= MINL || v2.SquareNorm <= MINL)
                                  goto RemovePoint;
                                  v1 = v1.Normalize(); // divide by zero if square norm is 0 (test above)
                                  v2 = v2.Normalize();
                                  var z = v1 ^ v2;
                                  if (Math.Abs(z) <= minsin && v1 * v2 < 0)
                                  goto RemovePoint;
                                  continue;
                                  RemovePoint: ;
                                  points.RemoveAt(i);
                                  if (points.Count < 3)
                                  return null;
                                  }

                                  A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

                                  L Steve EcholsS 2 Replies Last reply
                                  0
                                  • D Dalek Dave

                                    That's actually a nice bit of code. I have much to learm :sigh:

                                    ------------------------------------ I will never again mention that I was the poster of the One Millionth Lounge Post, nor that it was complete drivel. Dalek Dave CCC League Table Link CCC Link[^]

                                    L Offline
                                    L Offline
                                    Luc Pattyn
                                    wrote on last edited by
                                    #28

                                    it's like writing poetry, just keep scrapping the redundant bits until you start to like the result. Except you have to adhere to the original intentions... :)

                                    Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

                                    Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

                                    1 Reply Last reply
                                    0
                                    • D Dalek Dave

                                      It's neater.

                                      ------------------------------------ I will never again mention that I was the poster of the One Millionth Lounge Post, nor that it was complete drivel. Dalek Dave CCC League Table Link CCC Link[^]

                                      S Offline
                                      S Offline
                                      Super Lloyd
                                      wrote on last edited by
                                      #29

                                      Thanks! Glad someone agree! I think I was looking for a beating... but I have a hard time handling it! :laugh:

                                      A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

                                      1 Reply Last reply
                                      0
                                      • S Super Lloyd

                                        Indeed that will do! :thumbsup: :) However.... I do prefer goto to multiple nested statement! ;P

                                        A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

                                        P Offline
                                        P Offline
                                        Peter_in_2780
                                        wrote on last edited by
                                        #30

                                        Two comments. 1. Loops are only nested too deep when you need to indent each level by less than [insert favourite small number here, mine's 4] spaces to fit it on the screen. ;P The construct

                                        if (!test)
                                        goto next;
                                        do_stuff;
                                        next:

                                        is actually what a compiler* will emit if you feed it

                                        if (test)
                                        do_stuff;

                                        Ironic, huh? But maybe that's why we deal in the input to compilers and leave their output unseen. * for a typical target instruction set

                                        Software rusts. Simon Stephenson, ca 1994.

                                        S 1 Reply Last reply
                                        0
                                        • P PIEBALDconsult

                                          Until I did some refactoring today I had a method with three return statements! :omg: (They were to avoid a goto to abort a nested loop.)

                                          S Offline
                                          S Offline
                                          Super Lloyd
                                          wrote on last edited by
                                          #31

                                          Ho my god! That Is Bad! :laugh:

                                          A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station.... _________________________________________________________ My programs never have bugs, they just develop random features.

                                          1 Reply Last reply
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