A promise is association of an asynchronous operation to the possible execution paths that follow its resolution. It is also a holder for the value it was settled with. More...
Collaboration diagram for uel_promise_t:
Data Fields | |
| struct uel_promise_store * | source |
| The promise store from where this promise was issued. | |
| uel_promise_state_t | state |
| The current state of this promise. | |
| void * | value |
| The value this promise holds. Only meaningful if already settled. | |
| uel_promise_segment_t * | first_segment |
| The first segment to be processed when this promise settles. | |
| uel_promise_segment_t * | last_segment |
| The last segment to be processed when this promise settles. | |
Detailed Description
A promise is association of an asynchronous operation to the possible execution paths that follow its resolution. It is also a holder for the value it was settled with.
A promise is an object that can be in three different states:
- PENDING:
A promise is pending when its asynchronous operation has not completed yet and the promise does NOT hold any meaningful value.
If a segment handler returns a new promise, the original promise is considered pending while it awaits for the new promise to settle. - RESOLVED:
A promise is resolved when its asynchronous operation is successfully completed. It consistently holds whatever value it has been resolved with. - REJECTED:
A promise is rejected if its asynchronous operation could not complete successfully. Its value is set to whatever error it has been resolved with.
The documentation for this struct was generated from the following file:
- include/uevloop/utils/promise.h
