Donald Bruce Stewart wrote:

briqueabraque:

...

Hi,

How can I read a single character from standard output? I would like the user to press a single key and the reading function return imediately after that key is pressed.

so you want a function of type: IO Char

asking Hoogle (http://haskell.org/hoogle) we get: Prelude. getChar :: IO Char IO. hGetChar :: Handle -> IO Char

-- Don

getChar doesn't return until I press Enter. I need something that returns immediately after I press any key. Thanks, Maurício

On 10/23/06, Neil Mitchell wrote:

Hi

...

getChar doesn't return until I press Enter. I need something that returns immediately after I press any key.

It's a problem with buffering:

hSetBuffering stdin NoBuffering

This usually doesn't work on Windows: GHC 6.4.2 and 6.6: requires <enter> Hugs (console) Sept. 2006: requires <enter> WinHugs (GUI) Sept. 2006: works as expected But it seems to work on Linux: GHC 6.4.1 on Ubuntu 6.06: works as expected GHC 6.6 on Ubuntu 6.06: works as expected I am really interested in hearing of a solution that works on all platforms.

import IO main = do hSetBuffering stdin NoBuffering hGetChar stdin

Regards, Brian

Hi! Sorry if it is a bit off-topic in this thread. How can I input EOF symbol in WinHugs? Ctrl-Z and Ctrl-D don't work for me, so I can't use getContents function. Maybe there is a piece of documentation that I should read? Thanks! -- Dimitri

On 10/25/06, Neil Mitchell wrote:

...

How can I input EOF symbol in WinHugs?

No possible way. If you could type the NUL character that might possibly work, but even then 1) you can't, 2) it might not.

Do you have a particular need for typing the "end of getContents" in WinHugs? If so, I can open a bug and might be able to fix it for the next release.

Thank you! Surely I can get along without getContents in WinHugs: last time I thought about it I just wanted to show getContents function to my students (and using hGetContents on a file handle seems to be better example). Another function that could be useful when teaching IO is 'interact', and it seems that it's also impossible to use it without typing EOF (am I right?). So it would be nice to have a way to type EOF in WinHugs, but surely it's a feature one can live without. And thank you for WinHugs, it is really useful! -- Dimitri

Hi

...

Do you have a particular need for typing the "end of getContents" in WinHugs? If so, I can open a bug and might be able to fix it for the next release.

Thank you!

Fixed in the CVS version, the next release will allow Ctrl+Z or Ctrl+D to terminate an input stream. There were also a few additional fixes around the interact code that I made. If you want to use these fixes before the next release: http://haskell.org/hoogle/other/winhugs-interact-fixes-2006-oct-25.zip Extract winhugs.exe and replace the existing winhugs.exe in a Sep 2006 installation. Thanks Neil

On Wed, Oct 25, 2006 at 01:06:28AM +0400, Dimitri Timofeev wrote:

Sorry if it is a bit off-topic in this thread. How can I input EOF symbol in WinHugs? Ctrl-Z and Ctrl-D don't work for me, so I can't use getContents function. Maybe there is a piece of documentation that I should read?

does F6 work? it used to back with DOS something or another. John -- John Meacham - ⑆repetae.net⑆john⑈