Ian Lynagh
On Wed, Sep 26, 2012 at 03:30:50PM +0100, Jon Fairbairn wrote:
I have an application where I want to use relative paths in symlinks […]
So I want
makeRelative "/var/www/this_server/foo/bar/" "/var/www/this_server/bob"
to return "../../bob" […]
On posix at least, this would permit isRelative (makeRelative a b) always to be True, which is a pleasant property for it to have.
Is there any reason that System.FilePath.Posix.makeRelative should not do this? I don’t know enough about non-posix filesystems to know whether it even makes sense elsewhere.
Coincidentally, I needed this yesterday
So evidently it is useful, and at least two people think it should work this way :-)
(in my case, I know that both paths are absolute).
I wrote something similar, but with calls to isAbsolute and use of System.FilePath.makeRelative
One thing I wasn't sure of is what to do about different drives on Windows. Perhaps it would actually need to return a Maybe FilePath?
That would be an API change. Instead the documentation could still have a “where possible” clause, but add that it’s always possible on Posix. -- Jón Fairbairn Jon.Fairbairn@cl.cam.ac.uk