The following variables are used by patTemplate and cannot/should not be overridden:

    * PAT_ROW_VAR
    * PATTEMPLATE_VERSION (global scope)

If the attribute 'addSystemVars' is set to 'on', the following variables will be added:

    * PAT_LOOPS
    * PAT_IS_ODD
    * PAT_IS_EVEN
    * PAT_IS_FIRST
    * PAT_IS_LAST

Reserved tags are:

    * tmpl
    * sub
    * link
    * var
    * instance (not used, yet)
    * assign (not used, yet)

Reserved Attributes

1. VAR-Tag

    * copyfrom
    * copyfromtemplate
    * modifier
    * name
    * hidden

2. TMPL-Tag

    * addsystemvars
    * autoclear
    * autoload
    * child
    * conditiontmpl
    * conditionvar
    * loop
    * limit
    * maxloop (better name needed, e.g. 'chunk')
    * modulo
    * name
    * placeholder
    * reader
    * requiredvars
    * src
    * type
    * unusedvars
    * useglobals
    * varscope
    * visibility
    * whitespace

3. SUB-Tag

    * condition

4. LINK-Tag

    * src

5. INSTANCE-Tag (not implemented)

    * same as TMPL