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Section: 13.7 [networking.ts::async.exec.ctx] Status: WP Submitter: Jonathan Wakely Opened: 2020-03-17 Last modified: 2020-11-15
View all issues with WP status.
In the Networking TS, the service_already_exists exception type has no constructors declared. The logic_error base class is not default constructible, so service_already_exists's implicit default constructor is defined as deleted.
Implementations can add one or more private constructors that can be used by make_service, but there seems to be little benefit to that. The Boost.Asio type of the same name has a public default constructor.
[2020-04-18 Issue Prioritization]
Status set to Tentatively Ready after six positive votes on the reflector.
[2020-11-09 Approved In November virtual meeting. Status changed: Tentatively Ready → WP.]
This wording is relative to N4734.
Modify 13.7 [networking.ts::async.exec.ctx] p1, as indicated:
// service access template<class Service> typename Service::key_type& use_service(execution_context& ctx); template<class Service, class... Args> Service& make_service(execution_context& ctx, Args&&... args); template<class Service> bool has_service(const execution_context& ctx) noexcept; class service_already_exists : public logic_error
Add a new subclause after [async.exec.ctx.globals]:
13.7.6 Class service_already_exists [async.exec.ctx.except]
-1- The class service_already_exists defines the type of objects thrown as exceptions to report an attempt to add an existing service to an execution_context.service_already_exists();
-2- Postconditions: what() returns an implementation-defined NTBS.