commit 7b1b98c420355ccea98d8bd55c9193ee6b7cef97
author Eric Blake <eblake@redhat.com> Mon May 04 09:05:12 2015 -0600
committer Markus Armbruster <armbru@redhat.com> Tue May 05 18:39:00 2015 +0200
tree 0ceec0f9a47f2526cbc8feadf1d0faff480525af
parent ab045267447d52e63a79c0e18f89ae4411f5420b

qapi: Document new 'alternate' meta-type

The next patch will quit special-casing "'union':'Foo',
'discriminator':{}" and instead use "'alternate':'Foo'".

Separating docs from implementation makes it easier to focus
on wording without holding up code.  In particular, making
alternate a separate type makes for a nice type hierarchy:

          /-------- meta-type ------\
         /              |            \
    simple types    alternate     complex types
    |         |                   |           |
 built-in   enum             type(struct)   union
 |       \    /                            /    \
numeric  string                         simple  flat

A later patch will then clean up 'type' vs. 'struct'
confusion.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>