Common aspects

Each dynamic variable is identified by a unique name. Dynamic variables do not have a separate namespace. After evaluation, dynamic variables are handled like a static IzPack variable defined in a <variable><variables> section. This means they are visible like any other IzPack variable for replacing placeholders or as default value for user input fields assigning a value to a variable. 

If the name of a dynamic variable is also used in a variable definition in the <variables> section it is always used to set a default value of the dynamic variable with the same name rather than unsetting it during refreshing if there are no further conditions matching in the <dynamicvariables> section for that variable.

An IzPack installer refreshes dynamic variables on each panel change, which subsequently might affect a whole chain of conditions from the <conditions> section depending on these variables.

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If a dynamic variable is defined multiple times with the same key, all definitions are applied during refreshing in the order they are defined in the <dynamicvariables> section. If all of the currently applicable definitions would unset the variable it is unset, otherwise the last definition in the list "wins" during refreshing.

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