If you define a class without any constructor, the compiler will synthesize a constructor for you (and that will be a default constructor — i.e., one that doesn’t require any arguments). If, however, you do define a constructor, (even if it does take one or more arguments) the compiler will not synthesize a constructor for you — at that … Read more
The parent class’ constructor needs to be called before the subclass’ constructor. This will ensure that if you call any methods on the parent class in your constructor, the parent class has already been set up correctly. What you are trying to do, pass args to the super constructor is perfectly legal, you just need … Read more
In the line you are trying to invoke the default constructor of Rectangle. The compiler does not generate such a default constructor anymore, because your Rectangle has a user defined constructor that takes 2 parameters. Therefore, you need to specify the parameters, like The error I get when compiling your code is: Rectangle.cpp:8:15: error: no matching function for … Read more
Yes, you typically set this in a Makefile: One layer above you can also detect a suitable compiler via autoconf, cmake or whichever other meta-buildtool you might deploy. You of course play games as define g++11 as g++ -std=c++11 but such set-ups are not portable. g++-6.* will default to c++14 so at some this switch will be implicit. But it might take … Read more
A @RequiredArgsConstructor will be generated if no constructor has been defined. The Project Lombok @Data page explains: @Data is like having implicit @Getter, @Setter, @ToString, @EqualsAndHashCode and @RequiredArgsConstructor annotations on the class (except that no constructor will be generated if any explicitly written constructor exists).
If your compiler supports C++11 standard, there is a constructor inheritance using using (pun intended). For more see Wikipedia C++11 article. You write: This is all or nothing – you cannot inherit only some constructors, if you write this, you inherit all of them. To inherit only selected ones you need to write the individual constructors manually and … Read more
If your compiler supports C++11 standard, there is a constructor inheritance using using (pun intended). For more see Wikipedia C++11 article. You write: This is all or nothing – you cannot inherit only some constructors, if you write this, you inherit all of them. To inherit only selected ones you need to write the individual constructors manually and … Read more
The compiler is allowed to make one implicit conversion to resolve the parameters to a function. What this means is that the compiler can use constructors callable with a single parameter to convert from one type to another in order to get the right type for a parameter. Here’s an example class with a constructor that can … Read more
will try to initialise the array by calling a default constructor for node. You could either provide a default constructor or, rather verbosely, initialise all 100 elements explicitly or, since you’re using C++, use std::vector instead, appending to it (using push_back) at runtime
Can a struct have a constructor in C++? I have been trying to solve this problem but I am not getting the syntax.