clojure - Why do Haskell inferred types in return type polymorphism lead to runtime errors? -


Because of this I want to use Haskell because this gives me more information about my program at compiled time , By which I believe that this is the sound.

In addition, it will appear that Haskell is the optimum language in which to reach, (unlike the closure protocol - which can only be transmitted on the first argument).

When I find a Haskell polymorphic return value function such as read : 

  Read :: (read one) => String - & gt; A   
 with the following program:  
  addFive :: int - & gt; Int addFive x = x + 5 Main :: IO () Main = Print (Adfive (read "11") putStrLn (read "11")   
 I'm getting:  
  Runtime error ... program: prelog. Read: no parse   
 So I get a runtime error in a language with a better type of system.  
  (add-five [x] (+ 5 x) defln (println (add-five (read string), with the equivalent code in the closure "11"))) (printline (reading-string "11"))   
 gives:  
  16 11   
 My question  Why do the change in type of variation in the predicted types lead to runtime errors?  Should not they take them in compiling time?   
 
 
  read  type  
  (read one) = & Gt; String -> A   
 Which means it (compiler or interpreter, in fact) will select its return type according to the reference requirement.  
 Therefore, in  addFive (Read "11") , because  addFive  requires a  int , by compiler Selected  read  to  string - & gt; Int ; In  putStrLn (read "11") , it will be  string-> string  because  putStrLn  is a  string .  
 And this option happens at compile time, which means after compiling, the equivalent of your program  
  main = do print (addFive (readInt "11" )) PutStrLn (ReadString "11")   
 but it can not parse its argument as  readString  string  "11" , So it crashes at run time.  
 The fix for this problem is simple:  
  main = print (adfify (read "11")) putStrLn (read "\" 11 \ "")

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