constants

来源： https://stackoverflow.com/questions/22404997/warning-c4114-same-type-qualifier-used-more-than-once

来源： https://stackoverflow.com/questions/22404997/warning-c4114-same-type-qualifier-used-more-than-once

来源： https://stackoverflow.com/questions/22404997/warning-c4114-same-type-qualifier-used-more-than-once

来源： https://stackoverflow.com/questions/63442051/detecting-when-a-const-object-is-passed-to-a-function-that-mutates-it-in-dart

来源： https://stackoverflow.com/questions/63442051/detecting-when-a-const-object-is-passed-to-a-function-that-mutates-it-in-dart

来源： https://stackoverflow.com/questions/10818761/gcc-why-constant-variables-not-placed-in-rodata

问题 I was reading this answer on SO, and I was wondering why the fields are being explicitly declared as both static and const. Are const fields compile time constants in Dart? and if so doesn't that mean they are implicitly static? 回答1: You could, in theory, change Dart so that the const modifier implies static . This is a valid proposal and was actively discussed. There are two reasons why we prefer requiring the explicit static : It makes it clearer how these variables can be accessed (like

问题 I was studying "C complete reference" by Herbert Schildt and got stuck on the "const" explanation due by the pointer * he used at the same time with the const explanation. here is the code he used: #include <stdio.h> void dash(const char *str); int main() { dash("this is a test"); return 0; } void dash(const char *str) { while (*str) { if (*str == ' ') { printf("%c", '-'); } else { printf("%c", *str); } str++; } } I've tried to search about the pointer * and got some answers about adresses

问题 I was studying "C complete reference" by Herbert Schildt and got stuck on the "const" explanation due by the pointer * he used at the same time with the const explanation. here is the code he used: #include <stdio.h> void dash(const char *str); int main() { dash("this is a test"); return 0; } void dash(const char *str) { while (*str) { if (*str == ' ') { printf("%c", '-'); } else { printf("%c", *str); } str++; } } I've tried to search about the pointer * and got some answers about adresses

问题 Consider a standard for loop: for (int i = 0; i < 10; ++i) { // do something with i } I want to prevent the variable i from being modified in the body of the for loop. However, I cannot declare i as const as this makes the increment statement invalid. Is there a way to make i a const variable outside of the increment statement? 回答1: From c++20, you can use ranges::views::iota like this: for (int const i : std::views::iota(0, 10)) { std::cout << i << " "; // ok i = 42; // error } Here's a demo