Can C++ return type be template?

Can C++ return type be template?

Mind you – neither templates or function overloading can work by return type alone – he will have to also use different parameter types to distinguish the functions.

How do I get the return type of a function in C++?

To get the return type of foo , we simply use the following: using t = decltype(foo()); t now contains the return type.

Can functions return types?

A function may be defined to return any type of value, except an array type or a function type; these exclusions must be handled by returning a pointer to the array or function. When a function does not return a value, void is the type specifier in the function declaration and definition.

What’s wrong with C++ templates?

C++ templates can’t use normal run-time C++ code in the process of expanding, and suffer for it: for instance, the C++ factorial program is limited in that it produces 32-bit integers rather than arbitrary-length bignums.

What is difference between class template and function template in C++?

For normal code, you would use a class template when you want to create a class that is parameterised by a type, and a function template when you want to create a function that can operate on many different types.

How do I return a different data type in C++?

1. Create a data container (struct/class) containing the values you want to return. Then just update your function to return the class type rather than void and change your return value to return the class. This way you will be able to return all the data, but still only return one item.

Can we return string in C++?

Use the std::string func() Notation to Return String From Function in C++ Return by the value is the preferred method for returning string objects from functions. Since the std::string class has the move constructor, returning even the long strings by value is efficient.

Can you return a function in C++?

The return statement stops execution and returns to the calling function. When a return statement is executed, the function is terminated immediately at that point, regardless of whether it’s in the middle of a loop, etc.

What is the return type in C++?

The return type, which specifies the type of the value that the function returns, or void if no value is returned. In C++11, auto is a valid return type that instructs the compiler to infer the type from the return statement.

Which of the following is return value of functions in C++ if function not returning anything?

The result of a function with a return type but no return statement is undefined (except in C++ with main , where the return value is 0).

Should I avoid templates C++?

If a template tries to call + on a type that does not implement it, the result will be a compile-time error. In general, the static nature of templates allows for better compile-time checking and optimization. But there is nothing semantically wrong with your idea.

Are C++ templates compile or runtime?

So, there is no need for template evaluation at run time; the information is all known at compile time. If you were to instantiate templates at run time, you’d need the compiler and the linker services as part of the run time.

What is an example of a function template?

Function Templates We write a generic function that can be used for different data types. Examples of function templates are sort (), max (), min (), printArray (). // One function works for all data types. This would work

What is the difference between a function template and compiled code?

The difference is, the compiler does type checking before template expansion. The idea is simple, source code contains only function/class, but compiled code may contain multiple copies of same function/class. Function Templates We write a generic function that can be used for different data types.

What are some examples of templates in C++?

Examples of function templates are sort (), max (), min (), printArray (). Below is the program to implement Bubble Sort using templates in C++: Class Templates Like function templates, class templates are useful when a class defines something that is independent of the data type.

Is it possible to hide the return type of a template?

That cannot be done. The return type does not take part in type deduction, it is rather a result of having already matched the appropriate template signature. You can, nevertheless, hide it from most uses as: