Ch2, Ex12

Another version of (different from that in book)

try <s1> finally <s2> end

=================>
local T E in
   try
      <s1>
      T = false
   catch X then
      E = X
      T = true
   end
   <s2>
   if T then raise E end end
end 

Note: This exercise is missing from pdf version of the book online and 13th(unification problem) problem given in the book is the 12th one in pdf version.