std::coroutine_handle<Promise>::from_promise
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                    < cpp | coroutine | coroutine handle
                    
                                                            
                    |   static coroutine_handle from_promise( Promise& p );  | 
(since C++20) | |
Creates a coroutine_handle from the promise object of a coroutine. The created coroutine_handle refers the coroutine, and promise() returns a reference to p.
The behavior is undefined if p is not a reference to a promise object. This function is only provided for the primary template, i.e. specializations std::coroutine_handle<> and std::coroutine_handle<std::noop_coroutine_promise> do not have this function.
Parameters
| p | - | promise object of a coroutine to refer | 
Return value
A coroutine_handle referring the given coroutine.
Example
| This section is incomplete Reason: no example  | 
See also
  constructs a coroutine_handle object (public member function)  | |
|    [static]  | 
  imports a coroutine from a pointer  (public static member function)  | 
|    (C++20)  | 
  creates a coroutine handle that has no observable effects when resumed or destroyed  (function)  |