The Exists Condition
The Exists Condition can be used to check whether an object given by a nested parameter exists. Objects can be variables or files.
The Exists condition has been introduced in IzPack 5.0.
The nested elements of the Exists condition don't have any further attributes, but receive contents in the text embedded. IzPack variables are dynamically resolved for each value.
The variable name when a variable is to be checked whether it has been defined anywhere in the installation process.
The file name of a file which is to be checked to no exist.