actualize
set-union
with
key
by morphism
:set → key-set;
:elem → key;
∅ → ∅;
++ → ++;
# → #;
{ } → { };
∪ → ∪;
∩ → ∩;
\ → \;
-- → --;
∈ → ∈;
⊆ → ⊆;
a → key;
b → key0;
c → key1;
s → ks;
s0 → ks0;
s1 → ks1;
s2 → ks2
end actualize