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  4. Do you not understand booleans?

Do you not understand booleans?

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  • A alanevans

    This stuff drives me up the wall!!!

    bool is_queue_empty(void)
    {
    if (queue_length==0)
    {
    return true;
    }
    else
    {
    return false;
    }
    }

    Or this:

    bool counter_zero = counter==0 ? true : false;

    Or this:

    if (isUDPSetup()==true)
    {
    if ((forceSend==false))
    {
    ...
    }
    }

    (Variable names have been changed to protect the guilty) Or this *New one*:

    void setNeedsUpdate(bool update)
    {
    if ((update==true))
    NeedsUpdate=true;
    else
    NeedsUpdate=false;
    }

    S Offline
    S Offline
    Stefan_Lang
    wrote on last edited by
    #36

    Let's see... The first example I don't like - not for the if statement, but for the premature returns! Personally, I'd make it a one-liner, but I don't consider it all that horrible apart from the returns. The second ... well you could argue it's slightly more readable for inexperienced programmers, but if that is your purpose then you should write an if/else statement, not use ?:. The next is a double horror for comparing to boolean constants and unnecessary nesting, but I'd forgive the nesting for the off-chance of later maintenance introducing additional statements that depend on only the first condition. The last ... I suppose if you need to be able to run your code through really old C compilers that don't have their own built-in definitions of bool, true and false, then it makes sense not to assign one boolean variable blindly to another, but instead make an if/else statement to catch the case where the argument is neither true nor false. But even then, ==true is horrible. So, in short, all of the examples are indeed bad style, IMHO, but I agree with the others that no harm is done, except maybe a minor hit in maintenance effort for posting it in the Hall of Shame. ;) None of this will cause inefficiency either, since compilers are smart enough to produce efficient code even from that kind of code.

    1 Reply Last reply
    0
    • I Imperion

      The horrors I've seen:

      void setVisible(bool isVisible)
      {
      if(isVisible.ToString().ToLower() == "true")
      {
      this.Visible = true;
      }

      if(isVisible.ToString().ToLower() == "false")
      {
      this.Visible = false;
      }
      }

      S Offline
      S Offline
      Stefan_Lang
      wrote on last edited by
      #37

      :wtf: You're making this up, aren't you? :omg:

      I 1 Reply Last reply
      0
      • A alanevans

        This stuff drives me up the wall!!!

        bool is_queue_empty(void)
        {
        if (queue_length==0)
        {
        return true;
        }
        else
        {
        return false;
        }
        }

        Or this:

        bool counter_zero = counter==0 ? true : false;

        Or this:

        if (isUDPSetup()==true)
        {
        if ((forceSend==false))
        {
        ...
        }
        }

        (Variable names have been changed to protect the guilty) Or this *New one*:

        void setNeedsUpdate(bool update)
        {
        if ((update==true))
        NeedsUpdate=true;
        else
        NeedsUpdate=false;
        }

        P Offline
        P Offline
        patbob
        wrote on last edited by
        #38

        They were probable taught to program by some CS grad student who'd never done much significant real-world coding. That's right along the lines of the kinds of stupidity my teachers would teach us when I was an undergrad. Like everybody else, I picked up the stupidity too.. which lasted until I saw the other way and had to debug code to a schedule that was broken by such nonsense. I still do the compare to NULL sometimes, but I believe the C standard now defines NULL pointers as a false boolean value, so it is redundant and I'm trying to retrain away from it. Besides, boost smart pointers, which we use a lot in our code, have an override to generate a bool result for just such kinds of pointer checks and make comparing the raw pointer to NULL harder.

        We can program with only 1's, but if all you've got are zeros, you've got nothing.

        Y 1 Reply Last reply
        0
        • S Stefan_Lang

          :wtf: You're making this up, aren't you? :omg:

          I Offline
          I Offline
          Imperion
          wrote on last edited by
          #39

          I wish I was making this up. X| Although it's good for a laugh (then a cry) when we go in to fix a bug in his old modules.

          1 Reply Last reply
          0
          • A alanevans

            This stuff drives me up the wall!!!

            bool is_queue_empty(void)
            {
            if (queue_length==0)
            {
            return true;
            }
            else
            {
            return false;
            }
            }

            Or this:

            bool counter_zero = counter==0 ? true : false;

            Or this:

            if (isUDPSetup()==true)
            {
            if ((forceSend==false))
            {
            ...
            }
            }

            (Variable names have been changed to protect the guilty) Or this *New one*:

            void setNeedsUpdate(bool update)
            {
            if ((update==true))
            NeedsUpdate=true;
            else
            NeedsUpdate=false;
            }

            R Offline
            R Offline
            Rick Shaub
            wrote on last edited by
            #40

            Maybe he saw this boolean[^], got confused, and wanted to "make sure".

            S 1 Reply Last reply
            0
            • L Lost User

              Screw the compiler. It takes longer to read and understand, therefore it sucks.

              F Offline
              F Offline
              Fabio Franco
              wrote on last edited by
              #41

              And it obviously makes the reader scared of what else might come from that code who's developer can't understand even a booleans...

              "To alcohol! The cause of, and solution to, all of life's problems" - Homer Simpson

              M 1 Reply Last reply
              0
              • A alanevans

                This stuff drives me up the wall!!!

                bool is_queue_empty(void)
                {
                if (queue_length==0)
                {
                return true;
                }
                else
                {
                return false;
                }
                }

                Or this:

                bool counter_zero = counter==0 ? true : false;

                Or this:

                if (isUDPSetup()==true)
                {
                if ((forceSend==false))
                {
                ...
                }
                }

                (Variable names have been changed to protect the guilty) Or this *New one*:

                void setNeedsUpdate(bool update)
                {
                if ((update==true))
                NeedsUpdate=true;
                else
                NeedsUpdate=false;
                }

                R Offline
                R Offline
                rcampbell12
                wrote on last edited by
                #42

                Hey, you're coding in a language that I don't use, but I'm totally with you. This is one of my pet peeves, too. One of my languages is Visual FoxPro, which has the "Immediate IF" ternary function, IIF: IIF(expr, a, b) If expr is true, a is returned, otherwise b is returned. So what I see is people doing this: MyBoolVar = IIF(SomeVar = 2, .t., .f.) Which could be simplified to: MyBoolVar = SomeVar = 2 Much cleaner. Or they expand it into a regular IF statement similar to what you posted. When I see this it does worry me. If programming should result from logical thinking and a programmer has trouble understanding logical values (boolean values), then should we wonder about the rest of their skills?

                1 Reply Last reply
                0
                • R Rick Shaub

                  Maybe he saw this boolean[^], got confused, and wanted to "make sure".

                  S Offline
                  S Offline
                  Stefan_Lang
                  wrote on last edited by
                  #43

                  Wow - that link is worthy of a top position in the Hall of Shame all by itself! :omg:

                  1 Reply Last reply
                  0
                  • L Lost User

                    Yes, I suppose this simply comes from the old C++ days where there was no boolean type. To avoid side effects or compiler specific behavior, I always explicitly specified what I was testing. But I would write it like this:

                    if((flag1 == true) &&
                    (flag2 == true) &&
                    (flag3 == true))
                    {
                    ...
                    }

                    Usually it does not look so uniform. If I really had so many different flags, I would think about using a flag word and testing all flags in one go.

                    And from the clouds a mighty voice spoke:
                    "Smile and be happy, for it could come worse!"

                    And I smiled and was happy
                    And it came worse.

                    K Offline
                    K Offline
                    Kabwla Phone
                    wrote on last edited by
                    #44

                    (edit: I posted this as a reply to a message that is now now longer there, oh well) I do not write out the boolean, but I do write each condition on a new line. In addition to that, I start the new line with the operator, this way, it is very easy to see at the beginning of the line that it is a continuation of the previous line, and what the operation is:

                    if( flag1
                    && (someOtherFlagThatWillSqrewWithTheLayout == MagicNumbers.Ten)
                    && (flag3 == somethingElseCompletely))
                    {
                    ...
                    }

                    I use this style with anything that will make a line of code too long:

                    //Contrived Deep Nesting, line too long
                    var firstChildRow= SomeTypedDataSetWithSillyLongNameThatFillsTheEntireCodeWindow.Tables[0].ChildRelations[0].ChildTable.Rows[0];
                    //Broken up for readability. Note that I start with the 'dot'.
                    var firstChildRow= SomeTypedDataSetWithSillyLongNameThatFillsTheEntireCodeWindow
                    .Tables[0]
                    .ChildRelations[0]
                    .ChildTable
                    .Rows[0];

                    1 Reply Last reply
                    0
                    • A alanevans

                      This stuff drives me up the wall!!!

                      bool is_queue_empty(void)
                      {
                      if (queue_length==0)
                      {
                      return true;
                      }
                      else
                      {
                      return false;
                      }
                      }

                      Or this:

                      bool counter_zero = counter==0 ? true : false;

                      Or this:

                      if (isUDPSetup()==true)
                      {
                      if ((forceSend==false))
                      {
                      ...
                      }
                      }

                      (Variable names have been changed to protect the guilty) Or this *New one*:

                      void setNeedsUpdate(bool update)
                      {
                      if ((update==true))
                      NeedsUpdate=true;
                      else
                      NeedsUpdate=false;
                      }

                      N Offline
                      N Offline
                      Nunnenkamp
                      wrote on last edited by
                      #45

                      void setNeedsUpdate(bool update)
                      {
                      if ((update==true))
                      NeedsUpdate=true;
                      else
                      NeedsUpdate=false;
                      }

                      This would be better if they returned it too. Nothing like getting back what you put into it.

                      bool setNeedsUpdate(bool update)
                      {
                      if ((update==true))
                      NeedsUpdate=true;
                      else
                      NeedsUpdate=false;
                      return NeedsUpdate;
                      }

                      F Y 2 Replies Last reply
                      0
                      • N Nunnenkamp

                        void setNeedsUpdate(bool update)
                        {
                        if ((update==true))
                        NeedsUpdate=true;
                        else
                        NeedsUpdate=false;
                        }

                        This would be better if they returned it too. Nothing like getting back what you put into it.

                        bool setNeedsUpdate(bool update)
                        {
                        if ((update==true))
                        NeedsUpdate=true;
                        else
                        NeedsUpdate=false;
                        return NeedsUpdate;
                        }

                        F Offline
                        F Offline
                        fjdiewornncalwe
                        wrote on last edited by
                        #46

                        The second is better than the first. At least if you're going to set the value in this ridiculous fashion, make sure that it worked. :)

                        I wasn't, now I am, then I won't be anymore.

                        1 Reply Last reply
                        0
                        • L Lost User

                          Yes, I suppose this simply comes from the old C++ days where there was no boolean type. To avoid side effects or compiler specific behavior, I always explicitly specified what I was testing. But I would write it like this:

                          if((flag1 == true) &&
                          (flag2 == true) &&
                          (flag3 == true))
                          {
                          ...
                          }

                          Usually it does not look so uniform. If I really had so many different flags, I would think about using a flag word and testing all flags in one go.

                          And from the clouds a mighty voice spoke:
                          "Smile and be happy, for it could come worse!"

                          And I smiled and was happy
                          And it came worse.

                          A Offline
                          A Offline
                          Addy Tas
                          wrote on last edited by
                          #47

                          I came from the same dark ages and indeed untill some time ago i also had the tendency to check the boolean value. Particularly the BOOL was a nasty one as you could (with good sense) only check that to FALSE. One other 'trick' i got used to apply was swapping the variable and the value E.g.

                          if(FALSE != flag)
                          {

                          Logically this seems a bit odd but then again it did protect me against typo's like:

                          if( flag = FALSE)
                          {

                          Today this will generate a compiler warning but that has not always been the case and if you have a special vendor type compiler; you may still face the same. Why check on FALSE? Simple; that was defined (as 0), any one could set the BOOL to TRUE, 1, 2 etc. Don't you love the compilers of today? Or better yet, those of tomorrow? Cheers, AT

                          Cogito ergo sum

                          1 Reply Last reply
                          0
                          • P PIEBALDconsult

                            CDP1802 wrote:

                            why not if (flag == true)?

                            Indeed, I prefer that when writing in C. One thing that drives me nuts with C is reading things like:

                            char* s = ...

                            if ( s ) ...

                            :mad:

                            A Offline
                            A Offline
                            Addy Tas
                            wrote on last edited by
                            #48

                            That in combination with the inabiliy to properly initialize a variable has ruined more than one day... Cheers, AT

                            Cogito ergo sum

                            1 Reply Last reply
                            0
                            • A alanevans

                              This stuff drives me up the wall!!!

                              bool is_queue_empty(void)
                              {
                              if (queue_length==0)
                              {
                              return true;
                              }
                              else
                              {
                              return false;
                              }
                              }

                              Or this:

                              bool counter_zero = counter==0 ? true : false;

                              Or this:

                              if (isUDPSetup()==true)
                              {
                              if ((forceSend==false))
                              {
                              ...
                              }
                              }

                              (Variable names have been changed to protect the guilty) Or this *New one*:

                              void setNeedsUpdate(bool update)
                              {
                              if ((update==true))
                              NeedsUpdate=true;
                              else
                              NeedsUpdate=false;
                              }

                              K Offline
                              K Offline
                              KP Lee
                              wrote on last edited by
                              #49

                              How about "if (!(forceSend==true))" ? :doh:

                              1 Reply Last reply
                              0
                              • M Member 3687319

                                And I think your reasoning would be wrong. It IS more clear to write if (X==true). Just because you don't like it does not mean it is not more clear, especially to junior programmers. I am the senior lead and I instruct ALL of our programmers under me to write if (X==true). It doesn't cost the compiler anything and it makes it understandable by even the junior most person quickly. It is all about proper maintenance and thinking about the coder behind you instead of just yourself. X is a variable so comparing it like another variable is both consistent and readable.

                                B Offline
                                B Offline
                                BobJanova
                                wrote on last edited by
                                #50

                                This is, at best, a matter of opinion. For me it is less clear to write if(x == true) because I have to read twice as much text to get the meaning &dnash; just as it's unclear to give a method a 300 character name. I have never met anyone who is confused by if(booleanVariable) and if they are then they shouldn't be programming until they learn the language they're using – if they have trouble reading that then do you really want them poking around your pointer code, or reflection in C#, or constructor injection frameworks, or any of the other million things any real world app has that are far more confusing? Readability is all about having a single, clear, unambiguous meaning for a statement as quickly as possible. if(x) and if(!x) are short, clear and obviously different from each other (as long as you're using a font where ! is more than 2 pixels wide, heh). if(x == true) adds nothing, is easier to mix up with closely related but different statements (if(x = true) or if(x == True) or if(x == "true") etc) and doesn't immediately show that x is a boolean or castable to one until you read the whole thing. You are on your way to becoming one of the micromanaging senior leads who appear on The Daily WTF issuing that kind of order based on your personal opinion of readability.

                                1 Reply Last reply
                                0
                                • L Lost User

                                  Fine. Now what if a is a (signed) integer and has a negative value? Or what if a is a pointer which is currently NULL? Without having defined any value for TRUE or FALSE and without knowing how NULL was defined somewhere deep in the libraries, how do you now know which code will be executed and which not? Even if NULL is usually defined as 0x00, you cannot expect this to be true for every compiler. And what can happen if you use another compiler?

                                  int* a = NULL;
                                  int b = -42;

                                  if(a)
                                  {
                                  // We should not need to know how NULL is defined and therefore can never know wether
                                  // or not this code block will ever be entered
                                  }

                                  if(a == NULL)
                                  {
                                  // Now we explicitly compared with NULL and it is clear when this code will be executed
                                  }

                                  if(b)
                                  {
                                  // Negative values are undefined and it is up to the compiler wether a negative value is
                                  // seen as 'true' or as 'false'
                                  }

                                  if(b < 0)
                                  {
                                  // Explicitly testing the variable again removes all uncertainties
                                  }

                                  And from the clouds a mighty voice spoke:
                                  "Smile and be happy, for it could come worse!"

                                  And I smiled and was happy
                                  And it came worse.

                                  B Offline
                                  B Offline
                                  BobJanova
                                  wrote on last edited by
                                  #51

                                  Hey, I went and looked this up, the standard states explicitly that "In both forms, the first substatement is executed if the expression compares unequal to 0." http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1548.pdf[^] page 147 That is, negative numbers are defined by standard to be true for conditional expressions.

                                  1 Reply Last reply
                                  0
                                  • F Fabio Franco

                                    And it obviously makes the reader scared of what else might come from that code who's developer can't understand even a booleans...

                                    "To alcohol! The cause of, and solution to, all of life's problems" - Homer Simpson

                                    M Offline
                                    M Offline
                                    mostlyharmless1964
                                    wrote on last edited by
                                    #52

                                    i might be showing my age here but there used to be a readability test known as "the telephone test" (from Kerningham and Plauger) - Read your code to someone over the phone. If they can't understand it, try writing the code again. admittedly this has its problems but one of the upshots was that you should just name your booleans for the thing they test and then it reads well. also, comparing to "== true" or "== false" obviously breaks this readability test :)

                                    F 1 Reply Last reply
                                    0
                                    • M mostlyharmless1964

                                      i might be showing my age here but there used to be a readability test known as "the telephone test" (from Kerningham and Plauger) - Read your code to someone over the phone. If they can't understand it, try writing the code again. admittedly this has its problems but one of the upshots was that you should just name your booleans for the thing they test and then it reads well. also, comparing to "== true" or "== false" obviously breaks this readability test :)

                                      F Offline
                                      F Offline
                                      Fabio Franco
                                      wrote on last edited by
                                      #53

                                      mostlyharmless1964 wrote:

                                      i might be showing my age here

                                      Wow, never heard of it. Was it the time when the compilers were birds inside stone cases? :laugh:

                                      "To alcohol! The cause of, and solution to, all of life's problems" - Homer Simpson

                                      1 Reply Last reply
                                      0
                                      • A alanevans

                                        This stuff drives me up the wall!!!

                                        bool is_queue_empty(void)
                                        {
                                        if (queue_length==0)
                                        {
                                        return true;
                                        }
                                        else
                                        {
                                        return false;
                                        }
                                        }

                                        Or this:

                                        bool counter_zero = counter==0 ? true : false;

                                        Or this:

                                        if (isUDPSetup()==true)
                                        {
                                        if ((forceSend==false))
                                        {
                                        ...
                                        }
                                        }

                                        (Variable names have been changed to protect the guilty) Or this *New one*:

                                        void setNeedsUpdate(bool update)
                                        {
                                        if ((update==true))
                                        NeedsUpdate=true;
                                        else
                                        NeedsUpdate=false;
                                        }

                                        C Offline
                                        C Offline
                                        Clive D Pottinger
                                        wrote on last edited by
                                        #54

                                        I fully agree. This kind of stuff makes the code SO hard to read. And so many people do this too - just look at all the examples you were able to find! Atrocious. When will people learn to put spaces around their operators !?!?! :cool:

                                        Clive Pottinger Victoria, BC

                                        1 Reply Last reply
                                        0
                                        • M Member 3687319

                                          And I think your reasoning would be wrong. It IS more clear to write if (X==true). Just because you don't like it does not mean it is not more clear, especially to junior programmers. I am the senior lead and I instruct ALL of our programmers under me to write if (X==true). It doesn't cost the compiler anything and it makes it understandable by even the junior most person quickly. It is all about proper maintenance and thinking about the coder behind you instead of just yourself. X is a variable so comparing it like another variable is both consistent and readable.

                                          R Offline
                                          R Offline
                                          RoelofDeVilliers
                                          wrote on last edited by
                                          #55

                                          Why do boolean variables exist? To store and retrieve boolean expressions (TRUTH values). They were invented SO THAT we can write code like

                                          if (X)

                                          otherwise we could just as well remove the boolean type and work with integer flags like

                                          if (X==1)

                                          This was one of the issues people had with C. No proper boolean type. But now we have a proper boolean type so don't reduce it to a "flag value" that needs to be compared to something to find the truth. It holds the truth all on its own. That's its job.

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