[Pmwiki-users] Re: Variable names

[Robert P. J. Day]

On Mon, 18 Oct 2004, Patrick R. Michaud wrote:

> On Mon, Oct 18, 2004 at 09:19:22AM -0500, Jonathan Scott Duff wrote:

> > In a system where you have well-defined concepts of pages and groups,
> > $Group makes sense, but $Name does not. I suggest $Page instead.

> There are several problems with $Page -- the biggest being
> that, for obvious reasons, there are a *lot* of variables that begin
> with "Page" ($PageEditFmt, $PageNameChars, $PageNotFound, $PageUrl,
> $PageAttributes, etc.).  Thus, in order for this to work the '$Page'
> substitution would really need to take place *after* checking for
> all of the other substitutions, or we do some pattern trickery to make
> the '$Page' we see isn't part of something larger.

that's an implementation detail of how you'd *affect* the change, and
has absolutely nothing to do with whether using $Page instead of $Name
is a better idea.  in effect, it's a non-argument.  (and the fact that
all these other variables start with the prefix "Page" is the best
argument *for* calling it $Page instead of $Name. :-)

let me put it another way.  if you could magically make that
substitution happen throughout all of PmWiki2, would you do it?  if
you answered "yes", then you make it happen and deal with the
difficulties.  saying it would be a difficult edit just isn't
persuasive.

> Beyond that, conceptually I've always felt that the term "page"
> includes the group it's in -- i.e., people will normally think of
> Main.WikiSandbox as a different "page" from PmWiki.WikiSandbox, even
> though they have the same "name".

the law of orthogonality clearly suggests that you have two variables:

  Group		JUST the group name
  Page		JUST the page name

think of it this way.  someone's street address consists of two
pieces of information:

  1) street name
  2) house number

if you combine those two, you get their address.  as i see it, Group
should correspond to street, and Page is the house number.  if you
need the full address, you add the two together.  no problem.  (and,
again, any difficulties in affecting the change are not an issue in
deciding whether or not this should be done -- only whether it's a
good idea or not.)

(and as a side note, conceptually, i would have considered $Page as
just the page name without the Group prefix.  i guess we all have
different philosophies.)

> Of course, PmWiki 1 uses "$Title" for this, which works okay except
> that "title" means something different in the context of HTML
> (<title>...</title>) and doesn't work at all if a page can specify
> its own [:title:], so I switched to $Name.  It's not too late to
> switch to something else, but it needs to be demonstrably clearer.

i think it already *is* demonstrably a better idea.  having a variable
whose name is $Name is begging for confusion and a lack of clarity.

rday