Re: [PATCH] Apply pattern-matching immediately beneath the stow directory.

[Sergiu Ivanov]

Hello,

On Wed, Sep 09, 2009 at 11:55:48AM +0200, Carl Fredrik Hammar wrote:
> On Wed, Sep 09, 2009 at 12:28:28AM +0300, Sergiu Ivanov wrote:
> > On Tue, Sep 08, 2009 at 01:55:41PM +0200, Carl Fredrik Hammar wrote:
>
> > > How about matching one component at a time?
> > > 
> > > For instance, given `*/*/*' you iterate through all files in the
> > > current directory and find matches to `*/' (the slash filters out
> > > non-directories).  For each match you recurse, making the match the
> > > current directory and with the pattern with the tested component removed,
> > > e.g. `*/*'.  The recursion continues until the pattern is static or
> > > there are no matches.
> > > 
> > > (Clarification: by current directory I don't mean the process' CWD,
> > > just the directory currently being iterated.)
> > 
> > That's exactly what I was talking about.  (Though I forgot to mention
> > some details you have mentioned.)  I just wanted to say that it is not
> > really efficient.
> > 
> > But, as I've said in another mail, I guess I should think about
> > efficiency differently in this case.  My initial goal was to just
> > modify the target of pattern-matching a bit.  I guess the extending
> > the functionality would be okay.
[...]
> Your mail gave me the impression that you wanted to iterate through all
> files in the directory tree but stopping no deeper than the number of
> components in the pattern.

> However, both this and my proposal (which you really intended), is
> just as efficient as the original implementation.  Matching PATTERN
> under all directories in stow, is equivalent to matching `*/PATTERN'
> in these implementations.  All proposed implementations would iterate
> the same number of directories, and filter the same number of paths.

This would be true, if the original pattern-matching feature
implementation could correctly interpret multi-component patterns.
However, AIUI from the source code, the existing version simply
iterates all sub-directories of stow/*/ and tries to match their names
against the pattern.  I compared the implementation that could deal
with multi-component patterns with the original implementation of the
pattern-matching feature and came to the conclusion multi-component
pattern support would require more effort.

I hope I understood what you had said correctly.

Regards,
scolobb