Concurrency support

Gabriel Gonzalez gabriel439 at
Mon Aug 26 05:04:36 BST 2013

I brought this up once before and I just discovered that Haskeline has a 
mailing list so I'm posting the followup here.  I'm going to paste my 
previous e-mail inline for the benefit of others:

> I'm trying to build a general-purpose concurrent terminal using 
> Haskeline and I encountered a problem I haven't been able to solve.
> I would like to be able to print text to the console while Haskeline 
> is waiting for input using `getInputLine`. Specifically, I would like 
> to print the text *above* the user's input line (or lines, if the user 
> is typing a really long command) without disturbing the user input.
> The only way I know how to do this correctly is to delete the user 
> input and prompt, print the desired text, and then reprint the user 
> input prompt beginning on the next line.  However, I don't think that 
> is possible using the current Haskeline API and I wanted to know if 
> you could suggest any alternative solutions. 

I still think the simplest solution is to provide a way to temporarily 
delete the prompt and restore it back again.  I've already gotten this 
to work with `readline` using this exact same trick, but I would prefer 
to wait for `haskeline` to incorporate a similar feature because 
`haskeline` is just plain better than `readline`.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>

More information about the Haskeline mailing list