Other Variables

$FmtV This variable is an array that is used for string substitutions at the end of a call to FmtPageName(). For each element in the array, the "key" (interpreted as a string) will be replaced by the corresponding "value". The variable is intended to be a place to store substitution variables that have frequently changing values (thus avoiding a rebuild of the variable cache). Also see $FmtP.
$FmtP This variable is an array that is used for pattern substitutions near the beginning of a call to FmtPageName. For each element in the array, the "key" (interpreted as a pattern) will be replaced by the corresponding value evaluated for the name of the current page. This is for instance used to handle$-substitutions that depend on the pagename passed to FmtPageName(). Also see $FmtV. $FmtPV
This variable is an array that is used for Page Variables. New variables can be defined with $FmtPV['$VarName'] = 'variable definition'; which can be used in markup with {$VarName}.  #example for "source" action$PageAttributes['passwdsource'] = "\$['Set new source password']"