follow-up about handling .info file and index

[Robert Goldman]

On 21 Mar 2018, at 14:09, Robert Dodier wrote:

> Thanks for your comments, Robert. I've revised the INFO-INDEX class
> and made it a lot simpler (and still working the same). For what it's
> worth, I've pasted it below.
>
> I noticed that UIOP:COPY-FILE doesn't seem to behave well if told to
> copy a file to itself -- it clobbers the file. That seems like
> unfriendly behavior; it seems better that either it should complain or
> do nothing.

My guess (Faré's is the authorized word) is that it's difficult to tell 
when you are copying a file onto itself, the reason being that telling 
when two pathnames co-refer is problematic.

I guess we could add an :if-exists argument (defaulting to :overwrite 
for backwards compatibility), and make :supersede and :error be options.

We can't do :append, because Faré has used some implementations' 
built-ins for efficiency.  If you add a feature request to the 
launchpad, or (even better) a merge request to the common-lisp.net 
gitlab, I'll see about getting it in there.

Best,
r

>
> Thanks for your help, I think I'm in good shape on this front now.
>
> best,
> Robert Dodier
>
> PS.
> ;; info-index.lisp -- ASDF component type for Maxima documentation 
> index
> ;; copyright 2018 by Robert Dodier
> ;; I release this work under terms of the GNU General Public License
>
> (require 'asdf)
> (require 'uiop)
>
> (in-package :asdf)
>
> (defclass info-index (cl-source-file) ())
>
> ;; An info index file is a Lisp source file, which is compiled
> ;; just the same as an ordinary Lisp file, with the additional
> ;; step of copying the .info to the same location to where the
> ;; compiler output will go.
>
> (defmethod perform ((o compile-op) (c info-index))
>   (let*
>     ((system-name (component-name (component-system c)))
>      (info-name (make-pathname :name system-name :type "info"))
>      (info-in-file (merge-pathnames info-name (first (input-files o 
> c))))
>      (info-out-file (merge-pathnames info-name (first (output-files o 
> c)))))
>     ;; INFO-IN-FILE and INFO-OUT-FILE should be different,
>     ;; but just to be safe, silently refuse to copy file to itself.
>     (unless (uiop:pathname-equal info-in-file info-out-file)
>       (uiop:copy-file info-in-file info-out-file))
>     (call-next-method)))