threads :: Name -> SymbolTable -> Int
threads name table = case Map.lookup name table of 
                     Nothing -> error "error: threads"
                     Just a -> snd a
threads :: Name -> SymbolTable -> Int
threads name table = case Map.lookup name table of 
                     Nothing -> error "error: threads"
                     Just a -> snd a
threads name table = case Map.lookup name table of 
                     Nothing -> error "error: threads"
                     Just a -> snd a