Why is `const int& k = i; ++i; ` possible?What is the difference between const and readonly?How to...

Short story about space worker geeks who zone out by 'listening' to radiation from stars

Generic lambda vs generic function give different behaviour

Go Pregnant or Go Home

The baby cries all morning

Personal Teleportation as a Weapon

Why is `const int& k = i; ++i; ` possible?

What is the opposite of 'gravitas'?

Confused about a passage in Harry Potter y la piedra filosofal

How can I replace every global instance of "x[2]" with "x_2"

Is there a good way to store credentials outside of a password manager?

The plural of 'stomach"

Is exact Kanji stroke length important?

Teaching indefinite integrals that require special-casing

Efficiently merge handle parallel feature branches in SFDX

Is it okay / does it make sense for another player to join a running game of Munchkin?

What is the oldest known work of fiction?

What't the meaning of this extra silence?

What would be the benefits of having both a state and local currencies?

Stereotypical names

Implement the Thanos sorting algorithm

What defines a dissertation?

There is only s̶i̶x̶t̶y one place he can be

Have I saved too much for retirement so far?

At which point does a character regain all their Hit Dice?



Why is `const int& k = i; ++i; ` possible?


What is the difference between const and readonly?How to convert a std::string to const char* or char*?Why can templates only be implemented in the header file?Meaning of 'const' last in a function declaration of a class?What is the difference between const int*, const int * const, and int const *?Why is “using namespace std” considered bad practice?define() vs constWhy does ++[[]][+[]]+[+[]] return the string “10”?Why are elementwise additions much faster in separate loops than in a combined loop?Why is it faster to process a sorted array than an unsorted array?













7















I am supposed to determine whether this function is syntactically correct:



int f3(int i, int j) { const int& k=i; ++i; return k; }



I have tested it out and it compiles with my main function.



I do not understand why this is so.



Surely by calling the function f3 I create copies of the variables iand j in a new memory space and setting const int& k=i I am setting the memory space of the newly created k to the exact the same space of the memory space of the copied i, therefore any change, i.e. the increment ++iwill result in ++k which is not possible given that it was set const



Any help is greatly appreciated










share|improve this question



























    7















    I am supposed to determine whether this function is syntactically correct:



    int f3(int i, int j) { const int& k=i; ++i; return k; }



    I have tested it out and it compiles with my main function.



    I do not understand why this is so.



    Surely by calling the function f3 I create copies of the variables iand j in a new memory space and setting const int& k=i I am setting the memory space of the newly created k to the exact the same space of the memory space of the copied i, therefore any change, i.e. the increment ++iwill result in ++k which is not possible given that it was set const



    Any help is greatly appreciated










    share|improve this question

























      7












      7








      7








      I am supposed to determine whether this function is syntactically correct:



      int f3(int i, int j) { const int& k=i; ++i; return k; }



      I have tested it out and it compiles with my main function.



      I do not understand why this is so.



      Surely by calling the function f3 I create copies of the variables iand j in a new memory space and setting const int& k=i I am setting the memory space of the newly created k to the exact the same space of the memory space of the copied i, therefore any change, i.e. the increment ++iwill result in ++k which is not possible given that it was set const



      Any help is greatly appreciated










      share|improve this question














      I am supposed to determine whether this function is syntactically correct:



      int f3(int i, int j) { const int& k=i; ++i; return k; }



      I have tested it out and it compiles with my main function.



      I do not understand why this is so.



      Surely by calling the function f3 I create copies of the variables iand j in a new memory space and setting const int& k=i I am setting the memory space of the newly created k to the exact the same space of the memory space of the copied i, therefore any change, i.e. the increment ++iwill result in ++k which is not possible given that it was set const



      Any help is greatly appreciated







      c++ syntax reference const






      share|improve this question













      share|improve this question











      share|improve this question




      share|improve this question










      asked 7 hours ago









      user9078057user9078057

      1168




      1168
























          1 Answer
          1






          active

          oldest

          votes


















          15















          the increment ++iwill result in ++k which is not possible given that it was set const




          That's a misunderstanding.



          You may not change the value of the object through k but it can still be changed through other means. In other words, ++k is not allowed but ++i is still allowed, which will indirectly modify the value of k.



          Here's a far-fetched analogy.



          You may look through the window of a store and see what's inside but you won't be able to change what's inside the store. However, an employee, who is inside the store, can change the contents of the store. You will see that change from
          outside. You have const access or view access to the store while the employee has non-const access or change access to the store.






          share|improve this answer





















          • 5





            Not so far-fetched. That's a good analogy.

            – user4581301
            7 hours ago











          • Note that this is so because i itself is not const. So we have a const reference a non-const object. Const objects are different.

            – David Schwartz
            7 hours ago











          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%2f55367062%2fwhy-is-const-int-k-i-i-possible%23new-answer', 'question_page');
          }
          );

          Post as a guest















          Required, but never shown

























          1 Answer
          1






          active

          oldest

          votes








          1 Answer
          1






          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes









          15















          the increment ++iwill result in ++k which is not possible given that it was set const




          That's a misunderstanding.



          You may not change the value of the object through k but it can still be changed through other means. In other words, ++k is not allowed but ++i is still allowed, which will indirectly modify the value of k.



          Here's a far-fetched analogy.



          You may look through the window of a store and see what's inside but you won't be able to change what's inside the store. However, an employee, who is inside the store, can change the contents of the store. You will see that change from
          outside. You have const access or view access to the store while the employee has non-const access or change access to the store.






          share|improve this answer





















          • 5





            Not so far-fetched. That's a good analogy.

            – user4581301
            7 hours ago











          • Note that this is so because i itself is not const. So we have a const reference a non-const object. Const objects are different.

            – David Schwartz
            7 hours ago
















          15















          the increment ++iwill result in ++k which is not possible given that it was set const




          That's a misunderstanding.



          You may not change the value of the object through k but it can still be changed through other means. In other words, ++k is not allowed but ++i is still allowed, which will indirectly modify the value of k.



          Here's a far-fetched analogy.



          You may look through the window of a store and see what's inside but you won't be able to change what's inside the store. However, an employee, who is inside the store, can change the contents of the store. You will see that change from
          outside. You have const access or view access to the store while the employee has non-const access or change access to the store.






          share|improve this answer





















          • 5





            Not so far-fetched. That's a good analogy.

            – user4581301
            7 hours ago











          • Note that this is so because i itself is not const. So we have a const reference a non-const object. Const objects are different.

            – David Schwartz
            7 hours ago














          15












          15








          15








          the increment ++iwill result in ++k which is not possible given that it was set const




          That's a misunderstanding.



          You may not change the value of the object through k but it can still be changed through other means. In other words, ++k is not allowed but ++i is still allowed, which will indirectly modify the value of k.



          Here's a far-fetched analogy.



          You may look through the window of a store and see what's inside but you won't be able to change what's inside the store. However, an employee, who is inside the store, can change the contents of the store. You will see that change from
          outside. You have const access or view access to the store while the employee has non-const access or change access to the store.






          share|improve this answer
















          the increment ++iwill result in ++k which is not possible given that it was set const




          That's a misunderstanding.



          You may not change the value of the object through k but it can still be changed through other means. In other words, ++k is not allowed but ++i is still allowed, which will indirectly modify the value of k.



          Here's a far-fetched analogy.



          You may look through the window of a store and see what's inside but you won't be able to change what's inside the store. However, an employee, who is inside the store, can change the contents of the store. You will see that change from
          outside. You have const access or view access to the store while the employee has non-const access or change access to the store.







          share|improve this answer














          share|improve this answer



          share|improve this answer








          edited 7 hours ago

























          answered 7 hours ago









          R SahuR Sahu

          169k1294193




          169k1294193








          • 5





            Not so far-fetched. That's a good analogy.

            – user4581301
            7 hours ago











          • Note that this is so because i itself is not const. So we have a const reference a non-const object. Const objects are different.

            – David Schwartz
            7 hours ago














          • 5





            Not so far-fetched. That's a good analogy.

            – user4581301
            7 hours ago











          • Note that this is so because i itself is not const. So we have a const reference a non-const object. Const objects are different.

            – David Schwartz
            7 hours ago








          5




          5





          Not so far-fetched. That's a good analogy.

          – user4581301
          7 hours ago





          Not so far-fetched. That's a good analogy.

          – user4581301
          7 hours ago













          Note that this is so because i itself is not const. So we have a const reference a non-const object. Const objects are different.

          – David Schwartz
          7 hours ago





          Note that this is so because i itself is not const. So we have a const reference a non-const object. Const objects are different.

          – David Schwartz
          7 hours ago




















          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%2f55367062%2fwhy-is-const-int-k-i-i-possible%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

          “%fieldName is a required field.”, in Magento2 REST API Call for GET Method Type The Next...

          How to change City field to a dropdown in Checkout step Magento 2Magento 2 : How to change UI field(s)...

          變成蝙蝠會怎樣? 參考資料 外部連結 导航菜单Thomas Nagel, "What is it like to be a...