% TAPL [bool typing]  Typed booleans

grammar
T {{ hol Typ }}, S, U :: Ty ::=                       {{ com types: }}
  | Bool                         ::   :: Bool          {{ com type of booleans }}


defns
Jtype :: '' ::= 

defn
G |- t : T :: :: typing :: T_ {{ com Typing }} by


----------------- :: True
G |- true : Bool
    
----------------- :: False
G |- false : Bool

G |- t1:Bool
G |- t2:T
G |- t3:T
------------------------------ :: If
G |- if t1 then t2 else t3 : T 
    

