Change only a specific Default Parameter on a function2019 Community Moderator ElectionUse of 'const' for...

function only contains jump discontinuity but is not piecewise continuous

Can I solder 12/2 Romex to extend wire 5 ft?

How can I conditionally format my HTML table?

An Undercover Army

Has Wakanda ever accepted refugees?

How to roleplay my character's ethics according to the DM when I don't understand those ethics?

Why are special aircraft used for the carriers in the United States Navy?

Deal the cards to the players

Find maximum of the output from reduce

School performs periodic password audits. Is my password compromised?

How can I be pwned if I'm not registered on the compromised site?

How does insurance birth control work?

Practical reasons to have both a large police force and bounty hunting network?

A bug in Excel? Conditional formatting for marking duplicates also highlights unique value

Caulking a corner instead of taping with joint compound?

What is a term for a function that when called repeatedly, has the same effect as calling once?

How will Occam's Razor principle work in Machine learning

Create chunks from an array

Formatting a table to look nice

Has a sovereign Communist government ever run, and conceded loss, on a fair election?

Relationship between the symmetry number of a molecule as used in rotational spectroscopy and point group

Number of folds to form a cube , using a square paper?

Difference between 'stomach' and 'uterus'

Why would the IRS ask for birth certificates or even audit a small tax return?



Change only a specific Default Parameter on a function



2019 Community Moderator ElectionUse of 'const' for function parametersUse 'class' or 'typename' for template parameters?Why can templates only be implemented in the header file?Why do we need virtual functions in C++?Where to put default parameter value in C++?Why does changing 0.1f to 0 slow down performance by 10x?QInputDialog Parameter DefaultsAre the days of passing const std::string & as a parameter over?Qt: How to call a set to a toString, return in get function and testing a boolCan`t overload the operator << for a my own class












9















I'm using qt and I am trying to use the QInputDialog::getText() function to get input from the user, from the Documentation the definition of the function is:



QString QInputDialog::getText(QWidget * parent, const QString & title, const QString & label, QLineEdit::EchoMode mode = QLineEdit::Normal, const QString & text = QString(), bool * ok = 0, Qt::WindowFlags flags = 0, Qt::InputMethodHints inputMethodHints = Qt::ImhNone)


and here is my code:



bool ok=0;
newAddress = QInputDialog::getText(0,"Enter an Address to Validate",
"Adress: comma separated (e.g Address line 1, Address line 2, City, Postal Code)"
,&ok);


but I get the Error:



error: no matching function for call to 'QInputDialog::getText(int, const char [29], const char [80], bool*)'
,&ok);
^


but when I pass in all the arguments before the *ok argument like:



bool ok=0;
newAddress = QInputDialog::getText(0,"Enter an Address to Validate",
"Adress: comma separated (e.g Address line 1, Address line 2, City, Postal Code)"
,QLineEdit::Normal,
QString(),&ok);


it works.



I really don't understand why cant I just change the default parameter I want and leave the rest as default?.










share|improve this question





























    9















    I'm using qt and I am trying to use the QInputDialog::getText() function to get input from the user, from the Documentation the definition of the function is:



    QString QInputDialog::getText(QWidget * parent, const QString & title, const QString & label, QLineEdit::EchoMode mode = QLineEdit::Normal, const QString & text = QString(), bool * ok = 0, Qt::WindowFlags flags = 0, Qt::InputMethodHints inputMethodHints = Qt::ImhNone)


    and here is my code:



    bool ok=0;
    newAddress = QInputDialog::getText(0,"Enter an Address to Validate",
    "Adress: comma separated (e.g Address line 1, Address line 2, City, Postal Code)"
    ,&ok);


    but I get the Error:



    error: no matching function for call to 'QInputDialog::getText(int, const char [29], const char [80], bool*)'
    ,&ok);
    ^


    but when I pass in all the arguments before the *ok argument like:



    bool ok=0;
    newAddress = QInputDialog::getText(0,"Enter an Address to Validate",
    "Adress: comma separated (e.g Address line 1, Address line 2, City, Postal Code)"
    ,QLineEdit::Normal,
    QString(),&ok);


    it works.



    I really don't understand why cant I just change the default parameter I want and leave the rest as default?.










    share|improve this question



























      9












      9








      9








      I'm using qt and I am trying to use the QInputDialog::getText() function to get input from the user, from the Documentation the definition of the function is:



      QString QInputDialog::getText(QWidget * parent, const QString & title, const QString & label, QLineEdit::EchoMode mode = QLineEdit::Normal, const QString & text = QString(), bool * ok = 0, Qt::WindowFlags flags = 0, Qt::InputMethodHints inputMethodHints = Qt::ImhNone)


      and here is my code:



      bool ok=0;
      newAddress = QInputDialog::getText(0,"Enter an Address to Validate",
      "Adress: comma separated (e.g Address line 1, Address line 2, City, Postal Code)"
      ,&ok);


      but I get the Error:



      error: no matching function for call to 'QInputDialog::getText(int, const char [29], const char [80], bool*)'
      ,&ok);
      ^


      but when I pass in all the arguments before the *ok argument like:



      bool ok=0;
      newAddress = QInputDialog::getText(0,"Enter an Address to Validate",
      "Adress: comma separated (e.g Address line 1, Address line 2, City, Postal Code)"
      ,QLineEdit::Normal,
      QString(),&ok);


      it works.



      I really don't understand why cant I just change the default parameter I want and leave the rest as default?.










      share|improve this question
















      I'm using qt and I am trying to use the QInputDialog::getText() function to get input from the user, from the Documentation the definition of the function is:



      QString QInputDialog::getText(QWidget * parent, const QString & title, const QString & label, QLineEdit::EchoMode mode = QLineEdit::Normal, const QString & text = QString(), bool * ok = 0, Qt::WindowFlags flags = 0, Qt::InputMethodHints inputMethodHints = Qt::ImhNone)


      and here is my code:



      bool ok=0;
      newAddress = QInputDialog::getText(0,"Enter an Address to Validate",
      "Adress: comma separated (e.g Address line 1, Address line 2, City, Postal Code)"
      ,&ok);


      but I get the Error:



      error: no matching function for call to 'QInputDialog::getText(int, const char [29], const char [80], bool*)'
      ,&ok);
      ^


      but when I pass in all the arguments before the *ok argument like:



      bool ok=0;
      newAddress = QInputDialog::getText(0,"Enter an Address to Validate",
      "Adress: comma separated (e.g Address line 1, Address line 2, City, Postal Code)"
      ,QLineEdit::Normal,
      QString(),&ok);


      it works.



      I really don't understand why cant I just change the default parameter I want and leave the rest as default?.







      c++ qt qt5






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited 19 hours ago







      Makhele Sabata

















      asked yesterday









      Makhele SabataMakhele Sabata

      8916




      8916
























          3 Answers
          3






          active

          oldest

          votes


















          12














          When you pass a value for a particular parameter that has a default argument, you have to pass values for all the default parameters before it. Otherwise, the value you have passed will be taken as the value for the first default parameter.



          So you have to do this:



          newAddress = QInputDialog::getText(
          0,
          "Enter an Address to Validate",
          "Adress: comma separated (e.g Address line 1, Address line 2, City, Postal Code)",
          QLineEdit::Normal,
          QString(),
          &ok);


          You can leave out passing values for the parameters after bool * parameter.



          The C++ standard states in [dcl.fct.default]/1




          Default arguments will be used in calls where trailing arguments are missing.







          share|improve this answer


























          • I worked with Python when i started learning programming, and it i had this functionality where you could pass the arguments by name. it would be nice if they had something like that in C++. Thanks for the answer I wasn't aware of the trailing arguments issue.

            – Makhele Sabata
            21 hours ago













          • You are welcome.

            – P.W
            21 hours ago



















          7














          In C++ you can only use (one or multiple) default parameters at the end of the parameter list. If you omit parameters in the middle, the compiler has no way of knowing, which argument belongs to which parameter. Therefore you have to specify the default parameters QLineEdit::Normal and QString() manually before passing &ok.



          In your not working case the compiler tries to match your bool pointer to the next type in the parameter list, which is QLineEdit::EchoMode and therefore not compatible.






          share|improve this answer































            1














            the error is beacuse of the optional paramteres:



            QString QInputDialog::getText(
            QWidget * parent,
            const QString & title,
            const QString & label,
            QLineEdit::EchoMode mode = QLineEdit::Normal,
            const QString& text = QString(),
            bool * ok = 0,
            Qt::WindowFlags flags = 0,
            Qt::InputMethodHints inputMethodHints = Qt::ImhNone)


            QInputDialog::getText(
            0,
            "Enter an Address to Validate",
            "Adress: comma separated (e.g Address line 1, Address line 2, City, Postal Code)",
            --> QLineEdit::EchoMode ??
            --> QString& text ??
            &ok);


            if you set one optional parameter, you have to set all the optional paramteters to the left of that, in your case QLineEdit::EchoMode and QString& text






            share|improve this answer























              Your Answer






              StackExchange.ifUsing("editor", function () {
              StackExchange.using("externalEditor", function () {
              StackExchange.using("snippets", function () {
              StackExchange.snippets.init();
              });
              });
              }, "code-snippets");

              StackExchange.ready(function() {
              var channelOptions = {
              tags: "".split(" "),
              id: "1"
              };
              initTagRenderer("".split(" "), "".split(" "), channelOptions);

              StackExchange.using("externalEditor", function() {
              // Have to fire editor after snippets, if snippets enabled
              if (StackExchange.settings.snippets.snippetsEnabled) {
              StackExchange.using("snippets", function() {
              createEditor();
              });
              }
              else {
              createEditor();
              }
              });

              function createEditor() {
              StackExchange.prepareEditor({
              heartbeatType: 'answer',
              autoActivateHeartbeat: false,
              convertImagesToLinks: true,
              noModals: true,
              showLowRepImageUploadWarning: true,
              reputationToPostImages: 10,
              bindNavPrevention: true,
              postfix: "",
              imageUploader: {
              brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
              contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
              allowUrls: true
              },
              onDemand: true,
              discardSelector: ".discard-answer"
              ,immediatelyShowMarkdownHelp:true
              });


              }
              });














              draft saved

              draft discarded


















              StackExchange.ready(
              function () {
              StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f55020088%2fchange-only-a-specific-default-parameter-on-a-function%23new-answer', 'question_page');
              }
              );

              Post as a guest















              Required, but never shown

























              3 Answers
              3






              active

              oldest

              votes








              3 Answers
              3






              active

              oldest

              votes









              active

              oldest

              votes






              active

              oldest

              votes









              12














              When you pass a value for a particular parameter that has a default argument, you have to pass values for all the default parameters before it. Otherwise, the value you have passed will be taken as the value for the first default parameter.



              So you have to do this:



              newAddress = QInputDialog::getText(
              0,
              "Enter an Address to Validate",
              "Adress: comma separated (e.g Address line 1, Address line 2, City, Postal Code)",
              QLineEdit::Normal,
              QString(),
              &ok);


              You can leave out passing values for the parameters after bool * parameter.



              The C++ standard states in [dcl.fct.default]/1




              Default arguments will be used in calls where trailing arguments are missing.







              share|improve this answer


























              • I worked with Python when i started learning programming, and it i had this functionality where you could pass the arguments by name. it would be nice if they had something like that in C++. Thanks for the answer I wasn't aware of the trailing arguments issue.

                – Makhele Sabata
                21 hours ago













              • You are welcome.

                – P.W
                21 hours ago
















              12














              When you pass a value for a particular parameter that has a default argument, you have to pass values for all the default parameters before it. Otherwise, the value you have passed will be taken as the value for the first default parameter.



              So you have to do this:



              newAddress = QInputDialog::getText(
              0,
              "Enter an Address to Validate",
              "Adress: comma separated (e.g Address line 1, Address line 2, City, Postal Code)",
              QLineEdit::Normal,
              QString(),
              &ok);


              You can leave out passing values for the parameters after bool * parameter.



              The C++ standard states in [dcl.fct.default]/1




              Default arguments will be used in calls where trailing arguments are missing.







              share|improve this answer


























              • I worked with Python when i started learning programming, and it i had this functionality where you could pass the arguments by name. it would be nice if they had something like that in C++. Thanks for the answer I wasn't aware of the trailing arguments issue.

                – Makhele Sabata
                21 hours ago













              • You are welcome.

                – P.W
                21 hours ago














              12












              12








              12







              When you pass a value for a particular parameter that has a default argument, you have to pass values for all the default parameters before it. Otherwise, the value you have passed will be taken as the value for the first default parameter.



              So you have to do this:



              newAddress = QInputDialog::getText(
              0,
              "Enter an Address to Validate",
              "Adress: comma separated (e.g Address line 1, Address line 2, City, Postal Code)",
              QLineEdit::Normal,
              QString(),
              &ok);


              You can leave out passing values for the parameters after bool * parameter.



              The C++ standard states in [dcl.fct.default]/1




              Default arguments will be used in calls where trailing arguments are missing.







              share|improve this answer















              When you pass a value for a particular parameter that has a default argument, you have to pass values for all the default parameters before it. Otherwise, the value you have passed will be taken as the value for the first default parameter.



              So you have to do this:



              newAddress = QInputDialog::getText(
              0,
              "Enter an Address to Validate",
              "Adress: comma separated (e.g Address line 1, Address line 2, City, Postal Code)",
              QLineEdit::Normal,
              QString(),
              &ok);


              You can leave out passing values for the parameters after bool * parameter.



              The C++ standard states in [dcl.fct.default]/1




              Default arguments will be used in calls where trailing arguments are missing.








              share|improve this answer














              share|improve this answer



              share|improve this answer








              edited 23 hours ago

























              answered yesterday









              P.WP.W

              16k31455




              16k31455













              • I worked with Python when i started learning programming, and it i had this functionality where you could pass the arguments by name. it would be nice if they had something like that in C++. Thanks for the answer I wasn't aware of the trailing arguments issue.

                – Makhele Sabata
                21 hours ago













              • You are welcome.

                – P.W
                21 hours ago



















              • I worked with Python when i started learning programming, and it i had this functionality where you could pass the arguments by name. it would be nice if they had something like that in C++. Thanks for the answer I wasn't aware of the trailing arguments issue.

                – Makhele Sabata
                21 hours ago













              • You are welcome.

                – P.W
                21 hours ago

















              I worked with Python when i started learning programming, and it i had this functionality where you could pass the arguments by name. it would be nice if they had something like that in C++. Thanks for the answer I wasn't aware of the trailing arguments issue.

              – Makhele Sabata
              21 hours ago







              I worked with Python when i started learning programming, and it i had this functionality where you could pass the arguments by name. it would be nice if they had something like that in C++. Thanks for the answer I wasn't aware of the trailing arguments issue.

              – Makhele Sabata
              21 hours ago















              You are welcome.

              – P.W
              21 hours ago





              You are welcome.

              – P.W
              21 hours ago













              7














              In C++ you can only use (one or multiple) default parameters at the end of the parameter list. If you omit parameters in the middle, the compiler has no way of knowing, which argument belongs to which parameter. Therefore you have to specify the default parameters QLineEdit::Normal and QString() manually before passing &ok.



              In your not working case the compiler tries to match your bool pointer to the next type in the parameter list, which is QLineEdit::EchoMode and therefore not compatible.






              share|improve this answer




























                7














                In C++ you can only use (one or multiple) default parameters at the end of the parameter list. If you omit parameters in the middle, the compiler has no way of knowing, which argument belongs to which parameter. Therefore you have to specify the default parameters QLineEdit::Normal and QString() manually before passing &ok.



                In your not working case the compiler tries to match your bool pointer to the next type in the parameter list, which is QLineEdit::EchoMode and therefore not compatible.






                share|improve this answer


























                  7












                  7








                  7







                  In C++ you can only use (one or multiple) default parameters at the end of the parameter list. If you omit parameters in the middle, the compiler has no way of knowing, which argument belongs to which parameter. Therefore you have to specify the default parameters QLineEdit::Normal and QString() manually before passing &ok.



                  In your not working case the compiler tries to match your bool pointer to the next type in the parameter list, which is QLineEdit::EchoMode and therefore not compatible.






                  share|improve this answer













                  In C++ you can only use (one or multiple) default parameters at the end of the parameter list. If you omit parameters in the middle, the compiler has no way of knowing, which argument belongs to which parameter. Therefore you have to specify the default parameters QLineEdit::Normal and QString() manually before passing &ok.



                  In your not working case the compiler tries to match your bool pointer to the next type in the parameter list, which is QLineEdit::EchoMode and therefore not compatible.







                  share|improve this answer












                  share|improve this answer



                  share|improve this answer










                  answered yesterday









                  AlbertMAlbertM

                  352210




                  352210























                      1














                      the error is beacuse of the optional paramteres:



                      QString QInputDialog::getText(
                      QWidget * parent,
                      const QString & title,
                      const QString & label,
                      QLineEdit::EchoMode mode = QLineEdit::Normal,
                      const QString& text = QString(),
                      bool * ok = 0,
                      Qt::WindowFlags flags = 0,
                      Qt::InputMethodHints inputMethodHints = Qt::ImhNone)


                      QInputDialog::getText(
                      0,
                      "Enter an Address to Validate",
                      "Adress: comma separated (e.g Address line 1, Address line 2, City, Postal Code)",
                      --> QLineEdit::EchoMode ??
                      --> QString& text ??
                      &ok);


                      if you set one optional parameter, you have to set all the optional paramteters to the left of that, in your case QLineEdit::EchoMode and QString& text






                      share|improve this answer




























                        1














                        the error is beacuse of the optional paramteres:



                        QString QInputDialog::getText(
                        QWidget * parent,
                        const QString & title,
                        const QString & label,
                        QLineEdit::EchoMode mode = QLineEdit::Normal,
                        const QString& text = QString(),
                        bool * ok = 0,
                        Qt::WindowFlags flags = 0,
                        Qt::InputMethodHints inputMethodHints = Qt::ImhNone)


                        QInputDialog::getText(
                        0,
                        "Enter an Address to Validate",
                        "Adress: comma separated (e.g Address line 1, Address line 2, City, Postal Code)",
                        --> QLineEdit::EchoMode ??
                        --> QString& text ??
                        &ok);


                        if you set one optional parameter, you have to set all the optional paramteters to the left of that, in your case QLineEdit::EchoMode and QString& text






                        share|improve this answer


























                          1












                          1








                          1







                          the error is beacuse of the optional paramteres:



                          QString QInputDialog::getText(
                          QWidget * parent,
                          const QString & title,
                          const QString & label,
                          QLineEdit::EchoMode mode = QLineEdit::Normal,
                          const QString& text = QString(),
                          bool * ok = 0,
                          Qt::WindowFlags flags = 0,
                          Qt::InputMethodHints inputMethodHints = Qt::ImhNone)


                          QInputDialog::getText(
                          0,
                          "Enter an Address to Validate",
                          "Adress: comma separated (e.g Address line 1, Address line 2, City, Postal Code)",
                          --> QLineEdit::EchoMode ??
                          --> QString& text ??
                          &ok);


                          if you set one optional parameter, you have to set all the optional paramteters to the left of that, in your case QLineEdit::EchoMode and QString& text






                          share|improve this answer













                          the error is beacuse of the optional paramteres:



                          QString QInputDialog::getText(
                          QWidget * parent,
                          const QString & title,
                          const QString & label,
                          QLineEdit::EchoMode mode = QLineEdit::Normal,
                          const QString& text = QString(),
                          bool * ok = 0,
                          Qt::WindowFlags flags = 0,
                          Qt::InputMethodHints inputMethodHints = Qt::ImhNone)


                          QInputDialog::getText(
                          0,
                          "Enter an Address to Validate",
                          "Adress: comma separated (e.g Address line 1, Address line 2, City, Postal Code)",
                          --> QLineEdit::EchoMode ??
                          --> QString& text ??
                          &ok);


                          if you set one optional parameter, you have to set all the optional paramteters to the left of that, in your case QLineEdit::EchoMode and QString& text







                          share|improve this answer












                          share|improve this answer



                          share|improve this answer










                          answered yesterday









                          ΦXocę 웃 Пepeúpa ツΦXocę 웃 Пepeúpa ツ

                          33.8k113965




                          33.8k113965






























                              draft saved

                              draft discarded




















































                              Thanks for contributing an answer to Stack Overflow!


                              • Please be sure to answer the question. Provide details and share your research!

                              But avoid



                              • Asking for help, clarification, or responding to other answers.

                              • Making statements based on opinion; back them up with references or personal experience.


                              To learn more, see our tips on writing great answers.




                              draft saved


                              draft discarded














                              StackExchange.ready(
                              function () {
                              StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f55020088%2fchange-only-a-specific-default-parameter-on-a-function%23new-answer', 'question_page');
                              }
                              );

                              Post as a guest















                              Required, but never shown





















































                              Required, but never shown














                              Required, but never shown












                              Required, but never shown







                              Required, but never shown

































                              Required, but never shown














                              Required, but never shown












                              Required, but never shown







                              Required, but never shown







                              Popular posts from this blog

                              El tren de la libertad Índice Antecedentes "Porque yo decido" Desarrollo de la...

                              Puerta de Hutt Referencias Enlaces externos Menú de navegación15°58′00″S 5°42′00″O /...

                              Castillo d'Acher Características Menú de navegación