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fsdk::Promise< T > Class Template Reference

Promise class to support asynchronous data retrieval Look into std::promise semantics to understand it. More...

`#include <Future.h>`

Inheritance diagram for fsdk::Promise< T >:

## Public Types
using | Error = PromiseError
| Alias for associated error type.
using | DataType = T
| Alias for stored data type.

## Public Member Functions
| Promise () noexcept
| Constructor for empty Promise.
| Promise (Promise &&) noexcept
Promise & | operator= (Promise &&) noexcept
Result< Error > | cancel () noexcept
| Cancel method. Think of it as acceptance of cancel requested by. More...
Result< Error > | fail () noexcept
| Fail method. Think of it as valid failure to run some promised function. Only makes sense if underlying state is Promised. More...
Result< Error > | fulfill (DataType &&promisedData) noexcept
| Fulfill promise with data. Only makes sense if underlying state is Promised. More...
Future< DataType > | future (Result< Error > &error) noexcept
| Create tethered future object. Only makes sense if underlying state is Empty. More...
FuturePromiseState | state () const noexcept
| Returns current state of future-promise pair. More...

## Static Public Member Functions
static void | swap (Promise &first, Promise &second) noexcept
| Static method that swaps internal data between two passed promises.

## Detailed Description

### template<typename T>
class fsdk::Promise< T >

Promise class to support asynchronous data retrieval Look into std::promise semantics to understand it.

Note
  Is not instantiable using this header only.

Template Parameters

  T | data type to store.

## Member Function Documentation

template<typename T >

Result<Error> fsdk::Promise< T >::cancel | ( |  | ) |
| noexcept

Cancel method. Think of it as acceptance of cancel requested by.

See Also
  Future::cancel. Only makes sense if underlying state is CancelRequested.

Returns
  Result type containing

See Also
  Error code.

template<typename T >

Result<Error> fsdk::Promise< T >::fail | ( |  | ) |
| noexcept

Fail method. Think of it as valid failure to run some promised function. Only makes sense if underlying state is Promised.

Returns
  Result type containing

See Also
  Error code.

template<typename T >

Result<Error> fsdk::Promise< T >::fulfill | ( | DataType && | promisedData | ) |
| noexcept

Fulfill promise with data. Only makes sense if underlying state is Promised.

Parameters

  promisedData | Rvalue reference to promised data.

Returns
  Result type containing

See Also
  Error code.

template<typename T >

Future<DataType> fsdk::Promise< T >::future | ( | Result< Error > & | error | ) |
| noexcept

Create tethered future object. Only makes sense if underlying state is Empty.

Parameters

  error | Reference to error object to indicate of failure

Returns
  Future object tethered to this promise.

template<typename T >

FuturePromiseState fsdk::Promise< T >::state | ( |  | ) | const
| noexcept

Returns current state of future-promise pair.

Returns
  Current state

See Also
  FuturePromiseState.

The documentation for this class was generated from the following file:

- include/fsdk/Types/Future.h