When relying upon ECMAScript 6 features such as const, you should set this option so JSHint doesn’t raise unnecessary warnings. /*jshint esnext: true */ (Edit 2015.12.29: updated syntax to reflect @Olga’s comments) This option, as the name suggests, tells JSHint that your code uses ECMAScript 6 specific syntax. http://jshint.com/docs/options/#esversion Edit 2017.06.11: added another option based on this answer. While inline … Read more
In python, I want a class to have some “constants” (practically, variables) which will be common in all subclasses. Is there a way to do it with friendly syntax? Right now I use: and I’m wondering if there is a better way to do it or a way to do it without then having to … Read more
const_iterators don’t allow you to change the values that they point to, regular iterators do. As with all things in C++, always prefer const, unless there’s a good reason to use regular iterators (i.e. you want to use the fact that they’re not const to change the pointed-to value).
declares ptr a pointer to const int type. You can modify ptr itself but the object pointed to by ptr shall not be modified. While declares ptr a const pointer to int type. You are not allowed to modify ptr but the object pointed to by ptr can be modified. Generally I would prefer the declaration like this which make it easy to read and understand (read from right to left):
The realpath() function gives you the file-system path, with any symbolic links and directory traversing (e.g. ../../) resolved. The dirname() function gives you just the directory, not the file within it. __FILE__ is a magic constant that gives you the filesystem path to the current .php file (the one that __FILE__ is in, not the one it’s included by if it’s an … Read more
There is a misconception here with what const means, probably because it’s a little confusing that this works: but this doesn’t: The issue is that the array size in an array declaration must be a core constant expression. Simplified, that means an expression that’s evaluatable at compile time to be a constant. That is true in the … Read more
Apart from the apparent difference of having to declare the value at the time of a definition for a const VS readonly values can be computed dynamically but need to be assigned before the constructor exits.. after that it is frozen. const‘s are implicitly static. You use a ClassName.ConstantName notation to access them. There is a subtle difference. Consider a class defined … Read more
You don’t need an array of const objects. A pointer-to-const can point to either const or non-const objects; you can create a dynamic array and initialise a Chunk structure from it like this:
Every time I go from heavy C++ coding to Java, it takes me a little while to adapt to the lack of const-correctness in Java. This usage of const in C++ is much different than just declaring constant variables, if you didn’t know. Essentially, it ensures that an object is immutable when accessed through a special kind of pointer … Read more
A: The std::string class has a constructor that takes a char const*, so you simply create an instance to do your conversion. B: Instances of std::string have a c_str() member function that returns a char const* that you can use to convert back to char const*.