Andrew wrote:
>
> To whom it may concern,
>
> 'putStr' does not seem to work.
> I keep getting this:
> ERROR: Cannot find "show" function for:
> *** Expression : putChar
> *** Of type : Char -> IO ()
>
> Please help,
>
> Andrew Golightly
Top level expression need to be Show-able or of type IO a.
* If the top level expression is showable, then Hugs shows
it, using the show function.
* If the top level expression is of type IO, then Hugs
runs the IO action.
Example:
Prelude> putStr
ERROR: Cannot find "show" function for:
*** Expression : putStr
*** Of type : String -> IO ()
This is because putStr is now of a show-able type.
Prelude> putStr "Hello"
Hello
putStr with its argument is of type IO (), so hugs
runs the putStr action.
You also might want to try try the :s -u command;
it turns off the use of show.
There are many more examples in the documentation.
Hope this helps,
Andy
--
Principal Project Scientist, Pacific Software Research Center
Department of Computer Science and Engineering
Oregon Graduate Institute of Science & Technology
phone +1 503 748 7451 http://www.cse.ogi.edu/~andy
