template <typename Context>
basic_scan_arg class
Type-erased scanning argument.
Contains a pointer to the value contained in a scan_arg_store.
Public types
- class handle
Constructors, destructors, conversion operators
- basic_scan_arg() defaulted constexpr
- Construct a
basic_which doesn't contain an argument.scan_ arg - operator bool() const explicit constexpr noexcept
Public functions
-
template <typename Visitor>auto visit(Visitor&& vis) → decltype(auto) constexpr
Function documentation
template <typename Context>
scn::basic_scan_arg::operator bool() const explicit constexpr noexcept
| Returns | true if *this contains an argument |
|---|
template <typename Context>
template <typename Visitor>
decltype(auto) scn::basic_scan_arg::visit(Visitor&& vis) constexpr
template <typename Visitor>
| Returns | vis(x), where x is either a reference to the value contained in *this, or a basic_scan_arg::. |
|---|
Visit a basic_ with Visitor. Calls vis with the value stored in *this. If no value is contained in *this, calls vis with a monostate.