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spawn (4 of 13 overloads)

Start a new stackful coroutine that executes on a given executor.

    typename Executor,
    typename StackAllocator,
    typename F,
    typename CompletionToken = default_completion_token_t<Executor>>
auto spawn(
    const Executor & ex,
    allocator_arg_t ,
    StackAllocator && stack_allocator,
    F && function,
    CompletionToken && token = default_completion_token_t< Executor >(),
    constraint_t< is_executor< Executor >::value||execution::is_executor< Executor >::value >  = 0);

This function is used to launch a new stackful coroutine using the specified stack allocator.



Identifies the executor that will run the stackful coroutine.


Denotes the allocator to be used to allocate the underlying coroutine's stack. The type must satisfy the stack-allocator concept defined by the Boost.Context library.


The coroutine function. The function must be callable the signature:

void function(basic_yield_context<Executor> yield);

The completion token that will handle the notification that the coroutine has completed. If the return type R of function is void, the function signature of the completion handler must be:

void handler(std::exception_ptr);

Otherwise, the function signature of the completion handler must be:

void handler(std::exception_ptr, R);
Completion Signature
void(std::exception_ptr, R)

where R is the return type of the function object.

Per-Operation Cancellation

The new thread of execution is created with a cancellation state that supports cancellation_type::terminal values only. To change the cancellation state, call the basic_yield_context member function reset_cancellation_state.