Release 0.9.9 and earlier
lxr.conf 'maps' is a great device to select a file among many directories based on the value of variables. It works fine when clicking on a link e.g. in an #include. You are warped directly to the desired file. But if you want to compare this file to another one using "diff", LXR is confused about the second target file, because it is unable to correctly generate the path to the second file: it uses the transformed path of the first file, then tries to apply 'maps' and very often discovers that the file designated by this multiple processed path does not exist.
How can we circumvent that? Comments and advice wanted.
There is an incomplete implementation of something (what? it is lost in time) in httpinit: a parameter named 'file' seems to be "reserved". Could it be used to keep the original path? The function mappath would then be applied in httpinit and the result used as the target file.
I have not yet thought about it, nor determined the exact circumstances under which the aforementioned error occurs. At least, I know of it in diff.
Before going ahead, I would appreciate collecting events where it has caused trouble.