Var :: PParser Int
pTVar = Parser $ \ts -> case ts of
                          (TVar s):ts' -> [((read.tail) s,ts')]
                          _            -> []



-- | generating AST


pTVar :: PParser Int
pTVar = Parser $ \ts -> case ts of
                          (TVar s):ts' -> [((read.tail) s,ts')]
                          _            -> []



-- | generating AST
pTVar = Parser $ \ts -> case ts of
                          (TVar s):ts' -> [((read.tail) s,ts')]
                          _            -> []



-- | generating AST