control :: Parser Control
control =  branch
       <|> cond
       <|> call
       <|> ret
       <?> "control-transfer"
control :: Parser Control
control =  branch
       <|> cond
       <|> call
       <|> ret
       <?> "control-transfer"
control =  branch
       <|> cond
       <|> call
       <|> ret
       <?> "control-transfer"