14 Apr
2011
14 Apr
'11
3:29 a.m.
On Wed, 13 Apr 2011, Nabil Alsharif wrote:
instance Storable myUnion where size _ = #{size my_union} -- <-- hsc2hs shortcut alignment _ = alignment undefined::CInt -- <-- What should this really be? peek ptr = do -- <-- How are you supposed to know which element to extract?
That's the great "feature" of C unions, that you cannot know that in general. You have to store somewhere else, in a boolean or flag set, whether the stored union value contains a 'char' or an 'int'.
poke ptr (I i) = poke ptr i -- <-- Or should this be #{poke my_union, i} ptr i ? poke ptr (C c) = poke ptr c