> Very belated code review of last version of the patch:
>
> * `is_globlist` is no longer needed
+
+>> Good :)
+
> * I don't understand why the pagespec match regexp is changed
> from having flags `igx` to `ixgs`. Don't see why you
> want `.` to match '\n` in it, and don't see any `.` in the regexp
> anyway?
+
+>> Because you have to define all the named pagespecs in the pagespec, you sometimes end up with very long pagespecs. I found it useful to split them over multiple lines. That didn't work at one point and I added the 's' to make it work. I may have further altered the regex since then to make the 's' redundant. Remove it and see if multi-line pagespecs still work. :)
+
+>>> Well, I can tell you that multi-line pagespecs are supported w/o
+>>> your patch .. I use them all the time. The reason I find your
+>>> use of `/s` unlikely is because without it `\s` already matches
+>>> a newline. Only if you want to treat a newline as non-whitespace
+>>> is `/s` typically necessary. --[[Joey]]
+
> * Some changes of `@_` to `%params` in `pagespec_makeperl` do not
> make sense to me. I don't see where \%params is defined and populated,
> except with `\$params{specFunc}`.
+
+>> I'm not a perl hacker. This was a mighty battle for me to get going.
+>> There is probably some battlefield carnage from my early struggles
+>> learning perl left here. Part of this is that @_ / @params already
+>> existed as a way of passing in extra parameters. I didn't want to
+>> pollute that top level namespace - just at my own parameter (a hash)
+>> which contained the data I needed.
+
+>>> I think I understand how the various `%params`
+>>> (there's not just one) work in your code now, but it's really a mess.
+>>> Explaining it in words would take pages.. It could be fixed by,
+>>> in `pagespec_makeperl` something like:
+>>>
+>>> my %specFuncs;
+>>> push @_, specFuncs => \%specFuncs;
+>>>
+>>> With that you have the hash locally available for populating
+>>> inside `pagespec_makeperl`, and when the `match_*` functions
+>>> are called the same hash data will be available inside their
+>>> `@_` or `%params`. No need to change how the functions are called
+>>> or do any of the other hacks.
+>>>
+>>> Currently, specFuncs is populated by building up code
+>>> that recursively calls `pagespec_makeperl`, and is then
+>>> evaluated when the pagespec gets evaluated. My suggested
+>>> change to `%params` will break that, but that had to change
+>>> anyway.
+>>>
+>>> It probably has a security hole, and is certianly inviting
+>>> one, since the pagespec definition is matched by a loose regexp (`.*`)
+>>> and then subject to string interpolation before being evaluated
+>>> inside perl code. I recently changed ikiwiki to never interpolate
+>>> user-supplied strings when translating pagespecs, and that
+>>> needs to happen here too. The obvious way, it seems to me,
+>>> is to not generate perl code, but just directly run perl code that
+>>> populates specFuncs.
+
> * Seems that the only reason `match_glob` has to check for `~` is
> because when a named spec appears in a pagespec, it is translated
> to `match_glob("~foo")`. If, instead, `pagespec_makeperl` checked
> for named specs, it could convert them into `check_named_spec("foo")`
> and avoid that ugliness.
+
+>> Yeah - I wanted to make named specs syntactically different on my first pass. You are right in that this could be made a fallback - named specs always override pagenames.
+
> * The changes to `match_link` seem either unecessary, or incomplete.
> Shouldn't it check for named specs and call
> `check_named_spec_existential`?
+
+>> An earlier version did. Then I realised it wasn't actually needed in that case - match_link() already included a loop that was like a type of existential matching. Each time through the loop it would
+>> call match_glob(). match_glob() in turn will handle the named spec. I tested this version briefly and it seemed to work. I remember looking at this again later and wondering if I had mis-understood
+>> some of the logic in match_link(), which might mean there are cases where you would need an explicit call to check_named_spec_existential() - I never checked it properly after having that thought.
+
+>>> In the common case, `match_link` does not call `match_glob`,
+>>> because the link target it is being asked to check for is a single
+>>> page name, not a glob.
+
> * Generally, the need to modify `match_*` functions so that they
> check for and handle named pagespecs seems suboptimal, if
> only because there might be others people may want to use named
> that is not a page name at all, and it could be weird
> if such a parameter were accidentially interpreted as a named
> pagespec. (But, that seems unlikely to happen.)
+
+>> Possibly. I'm not sure which I prefer between the current solution and that one. Each have advantages and disadvantages.
+>> It really isn't much code for the match functions to add a call to check_named_spec_existential().
+
+>>> But if a plugin adds its own match function, it has
+>>> to explicitly call that code to support named pagespecs.
+
> * I need to check if your trick to avoid infinite recursion
> works if there are two named specs that recursively
> call one-another. I suspect it does, but will test this
> myself..
->
+
+>> It worked for me. :)
+
+> * I also need to verify if memoizing the named pagespecs has
+> really guarded against very expensive pagespecs DOSing the wiki..
+
> --[[Joey]]
+>> There is one issue that I've been thinking about that I haven't raised anywhere (or checked myself), and that is how this all interacts with page dependencies.
+>> Firstly, I'm not sure anymore that the `pagespec_merge` function will continue to work in all cases.
+
+>>> The problem I can see there is that if two pagespecs
+>>> get merged and both use `~foo` but define it differently,
+>>> then the second definition might be used at a point when
+>>> it shouldn't (but I haven't verified that really happens).
+>>> That could certianly be a show-stopper. --[[Joey]]
+
+>> Secondly, it seems that there are two types of dependency, and ikiwiki
+>> currently only handles one of them. The first type is "Rebuild this
+>> page when any of these other pages changes" - ikiwiki handles this.
+>> The second type is "rebuild this page when set of pages referred to by
+>> this pagespec changes" - ikiwiki doesn't seem to handle this. I
+>> suspect that named pagespecs would make that second type of dependency
+>> more important. I'll try to come up with a good example. -- [[Will]]
+
+>>> Hrm, I was going to build an example of this with backlinks, but it
+>>> looks like that is handled as a special case at the moment (line 458 of
+>>> render.pm). I'll see if I can breapk
+>>> things another way. Fixing this properly would allow removal of that special case. -- [[Will]]
+
+>>>> I can't quite understand the distinction you're trying to draw
+>>>> between the two types of dependencies. Backlinks are a very special
+>>>> case though and I'll be suprised if they fit well into pagespecs.
+>>>> --[[Joey]]
+
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