On 30/12/2011 11:44, Frank Mittelbach wrote:
> Am 30.12.2011 10:46, schrieb Ulrike Fischer:
>> Hello,
>>
>> what is the recommended way to issue a \leavevmode in latex3?
> 
> I guess the answer is not yet. Eventually the underlying concept should
> be part of the galley module. But how this will provided in the end
> depends a little bit on how far we take this module. There have been two
> different implementations initially with somewhat different concepts and
> the new one by Joseph implements some but not all of the original one
> (for good reasons I would say).

In some parts of the coffin code, we do this 'directly' using

  \hbox_unpack:N \c_empty_box

As Frank says, the galley module contains \galley_leave_vmode:, but that
is not loaded by default.
-- 
Joseph Wright