### yield_context

Context object that represents the currently executing coroutine.

    typedef basic_yield_context< unspecified > yield_context;

##### Types

Name | Description
--- | ---
callee_type | The coroutine callee type, used by the implementation.
caller_type | The coroutine caller type, used by the implementation.

##### Member Functions

Name | Description
--- | ---
basic_yield_context [constructor] | Construct a yield context to represent the specified coroutine. — Construct a yield context from another yield context type.
operator[] | Return a yield context that sets the specified error_code.

The `basic_yield_context` class is used to represent the currently executing stackful coroutine. A `basic_yield_context` may be passed as a handler to an asynchronous operation. For example:

    template <typename Handler>
    void my_coroutine(basic_yield_context<Handler> yield)
    {
      ...
      std::size_t n = my_socket.async_read_some(buffer, yield);
      ...
    }

The initiating function (async_read_some in the above example) suspends the current coroutine. The coroutine is resumed when the asynchronous operation completes, and the result of the operation is returned.

##### Requirements

Header: `asio/spawn.hpp`

Convenience header: None