propagate_value

Gets the result of this as a Value, and transfers ownership of that value to the caller.

As with return_value, this is a generic low-level method; propagate_pointer and the like will usually be more useful for C code.

If the task resulted in an error, or was cancelled, then this will instead set throws and return false.

Since this method transfers ownership of the return value (or error) to the caller, you may only call it once.

Parameters:

this	a Task
value	return location for the Value

Returns:

true if this succeeded, false on error.