template<typename... T>
cti::result class

The result class can carry the three kinds of results an asynchronous operation possibly can return, it's implemented in a variant like data structure which is also specialized to hold arbitrary arguments.

Contents

The result can be in the following three states:

  • no result: If the operation didn't finish
  • a value: If the operation finished successfully
  • an exception: If the operation finished with an exception or was cancelled.

The interface of the result object is similar to the one proposed in the std::expected proposal:

result<std::string> result = make_result("Hello World!");
bool(result);
result.is_value();
result.is_exception();
*result; // Same as result.get_value()
result.get_value();
result.get_exception();

Public static functions

static auto from(T... values) -> result
Creates a present result from the given values.
static auto from(exception_arg_t, exception_t exception) -> result
Creates a present result from the given exception.
static auto empty() -> result
Creates an empty result.

Constructors, destructors, conversion operators

operator bool() const explicit constexpr noexcept
Returns true if the state of the result holds the result.

Public functions

void set_empty()
Set the result to an empty state.
void set_value(T... values)
Set the result to a the state which holds the corresponding value.
void set_exception(exception_t exception)
Set the result into a state which holds the corresponding exception.
void set_canceled()
Set the result into a state which holds the cancellation token.
auto is_empty() const -> bool noexcept
Returns true if the state of the result is empty.
auto is_value() const -> bool noexcept
Returns true if the state of the result holds the result.
auto is_exception() const -> bool noexcept
Returns true if the state of the result holds a present exception.
auto get_value() &noexcept -> decltype(auto)
Returns the values of the result, if the result doesn't hold the value the behaviour is undefined but will assert in debug mode.
auto get_value() const &noexcept -> decltype(auto)
Returns the values of the result, if the result doesn't hold the value the behaviour is undefined but will assert in debug mode.
auto get_value() &&noexcept -> decltype(auto)
Returns the values of the result, if the result doesn't hold the value the behaviour is undefined but will assert in debug mode.
auto operator*() &noexcept -> decltype(auto)
Returns the values of the result, if the result doesn't hold the value the behaviour is undefined but will assert in debug mode.
auto operator*() const &noexcept -> decltype(auto)
Returns the values of the result, if the result doesn't hold the value the behaviour is undefined but will assert in debug mode.
auto operator*() &&noexcept -> decltype(auto)
Returns the values of the result, if the result doesn't hold the value the behaviour is undefined but will assert in debug mode.
auto get_exception() &noexcept -> exception_t&
Returns the exception of the result, if the result doesn't hold an exception the behaviour is undefined but will assert in debug mode.
auto get_exception() const &noexcept -> exception_t const &
Returns the exception of the result, if the result doesn't hold an exception the behaviour is undefined but will assert in debug mode.
auto get_exception() &&noexcept -> exception_t&&
Returns the exception of the result, if the result doesn't hold an exception the behaviour is undefined but will assert in debug mode.