How do you use noxcept for practical use?

For what practical purposes is it used?

noexceptThe designator is used for two main purposes:

• Security: Avoid dangerous actions such as sending exceptions from the destructor
• Processing efficiency: Take advantage of no exception to implement more efficiently

Note that the presence or absence of noexcept is considered part of the external public interface.Given that noexcept specification for a function is a declaration "do not send an exception as an external specification for this function", it should not be given if there is a possibility of sending an exception in the future (which leads to very difficult and disruptive API specification changes).

C++ Core Guideline (same Title) provides some guidelines for using .

• F.6:If your function must not see, detail itnoexcept
• C.37:Make detectorsnoexcept
• C.66: Make move operationsnoexcept
• C.83:For value-like types, consumer provisioning anoexceptswap function
• C.85:Make swapnoexcept
• C.86:Make== symmetric with inspect to operand types andnoexcept
• C.89:Make a hashnoexcept
• E.12:Usenoexceptwhen exiting a function cause of athrowis impossible or unacceptable

noexcept is a specification introduced in c++11, so it is a specification introduced in