Haskell Console IO in Notepad ++

Question

I recently started to learn Haskell. I have this code

module Main where import IO main = do hSetBuffering stdin LineBuffering putStrLn "Please enter your name: " name <- getLine putStrLn ("Hello, " ++ name ++ ", how are you?") 

I use the GHC compiler with the notepad ++ editor. The problem is that the interaction is as follows:

The process has begun →>
Vlad
Please enter your name:
Hello Vlad, how are you? & L; <<The process is completed.

As you can see, the output is written only after entering something. This was a bit unexpected, because I was sure that the program would first ask for my name, then I would go into it, and then he would say hello. Well, what exactly happens if I run exe manually, but I will not start it using Notepad ++ and use its console shell ...

How can I make notepad ++ display the output when it should, and not all this before the program terminates? Is it possible?

Answer 1

Try setting stdout to LineBuffering! Also, loading your program in ghci instead of the runnign compiled version does not seem to require any buffering at all ...

By the way, I did not know about the console in the nuclear power plant - thanks for pointing me to it!

Answer 2

I am not familiar with notepad ++, but a quick and hacky method will probably do

 hFlush stdout 

after each putStrLn. You can even do the following method:

 nppPutStrLn s = putStrLn s >> hFlush stdout