Integrating editline with ghc

[Judah Jacobson]

On Jan 21, 2008 2:40 AM, Christian Maeder <Christian.Maeder at dfki.de> wrote:
> Judah Jacobson wrote:
> > I think it will be much simpler if we keep the readline and editline
> > packages as they are now, and possibly add a third readline-compat
> > package which can use either one as a dependency.  Then any project
> > (including GHC) can choose which of those packages to use, based on
> > API requirements and/or license issues.
>
> Could then editline go already into ghc-6.8.3, because interfaces don't
> change?
>
> Re-iterating, I would like to see your package readline-compat and hope
>  it will be sufficient for the packages Shellac and Shellac-readline.
> (Even better if the current package readline is renamed to old-readline
> and readline-compat to readline.)

Hmm...As Christian suggested to me in a private email, I was wrong in
my initial testing of Shellac-readline: it relies on a variable
(_history_max_entries) that is not in editline.  So I think we should
definitely keep the readline package the way that it is.

Luckily, there are other functions, giving the same functionality,
which are shared by readline and editline, and are scheduled to become
official parts of readline in a week or two; see
(http://www.nabble.com/Readline-read_history-and-write_history-addition-td14967976.html)
 I'll add those functions to the editline and readline-compat
packages.

> I wonder how many hackage packages have readline as build-depends (and
> how many of them would be content with readline-compat).
>
> Which version of editline to you require?
>
> Our newest version installed (under Solaris) is: editline.h,v 1.5
>
> Which include files are used on Macs?

On OS X 10.4, I have readline.h,v 1.11 as the libedit readline
compatibility header.  Can you please try linking a simple program
that uses System.Console.Editline.Readline on your Solaris machine and
see if it throws up any link errors?  If so, I may be able to fix
that.

Thanks,
-Judah