Using noexcept for functions that do not throw exceptions

Exception specification is a language feature that can enable performance improvements, but on the other hand, when done incorrectly, it can abnormally terminate the program. The exception specification from C++03, which allowed you to indicate what types of exceptions a function could throw, has been deprecated and replaced with the new C++11 noexcept specification. This specification only allows you to indicate that a function does not throw exceptions, but not the actual exceptions types that it throws. This recipe provides information about the modern exception specifications in C++, as well as guidelines on when to use them.

How to do it...

Use the following constructs to specify or query exception specifications:

• Use nothrow in a function declaration to indicate that the function is not throwing any exception:

  void func_no_throw() noexcept
  {
  }
  

• Use nothrow(expr) in a function declaration...