Proposal: Add --with-libedit flag to the readline package

Ian Lynagh igloo at earth.li
Fri Jan 11 10:56:03 EST 2008


Hi Judah,

On Wed, Jan 09, 2008 at 10:08:20AM -0800, Judah Jacobson wrote:
> 
>  - If it is libedit, we #ifdef out all of the functions not supported
> by libedit. (these are generally low-level APIs not needed by most
> applications, including ghci.) Otherwise, if we're linking against GNU
> readline, we support all the available APIs.
> 
> Thoughts?

I agree with Thorkil's message to the bug report (although I think the
library name should be libedit or editline - I'm a bit confused about
the relationship of the two).

If a Haskell library or program has a build-depends on readline, then it
should get the same functions everywhere; otherwise dependencies are
meaningless. If a program wants to support both libraries then it can do
something like

If flag(readline)
    Build-depends: readline
    CPP-flags: -DUSING_READLINE
Else
    Build-depends: editline
    CPP-flags: -DUSING_EDITLINE

Of course, a third library could do the above conditional dependency and
provide an interface to the intersection of readline and editline's
functionalities. Other programs can then use that third library.


Thanks
Ian



More information about the Libraries mailing list