bug#11764: Missing C API doc for accessing unknown number of values

[David Kastrup]

<URL:http://www.gnu.org/software/guile/manual/html_node/Multiple-Values.html#Multiple-Values>

provides scm_c_value_ref for accessing a particular value from a values
object.  There is no documented way for figuring out how many values
there are.  There is no documented way for getting the complete list of
values in an object (Guile itself uses scm_struct_ref (value,SCM_INUM0)).

While there is a macro VALUESP for figuring out whether an SCM is a
values object, it is not documented either.

-- 
David Kastrup