[pmwiki-users] What is the correct use of slashes

[K.A.Bouton]

Sorry to overwhelm the list with questions - but I am making great headway
in understanding this and getting it all set up

I want to sharing files across farm - eg Profiles

So - using this list advice I have put this in my farm/farmconfig.php

#1
$WikiLibDirs = array(&$WikiDir,
                  new PageStore("$FarmD/wiki.d/\$FullName"),
                  new PageStore("$FarmD/shared.d/\$FullName"),
                  new PageStore('$FarmD/wikilib.d/$FullName'));
                  
$group = FmtPageName('$Group', $pagename);
    if($action == 'edit' && $group == 'Profiles') 
     //$WikiLibDirs[] = $WikiDir;    (one user had this but it doesn't work
for me)
      $WikiDir = new PageStore("$FarmD/shared.d/\$FullName");

The above works for my setup (apparently)

However in pmwiki it says 

#2
WikiLibDirs = array($WikiDir, 
      new PageStore('/path/to/shared.d/$FullName'),
      new PageStore("$FarmD/wikilib.d/\$FullName"));

$group = FmtPageName('$Group', $pagename);
    if ($action == 'edit' && $group == 'Shared') 
      $WikiDir = new PageStore('/path/to/shared.d/$FullName');

This DOES NOT work for me.
Note the different use of slashes and single vs double quotes.
What do they mean and why does #1 work for my setup?
Is it wrong? Am I setting myself up for problems down the line?

Thanks

Katherine