Incorrect documentation for EnvironmentVariable operation

The documentation for the EnvironmentVariable operation has the optional (boolean) arguments, persistent and system.

The format [[persistent] system] suggests:
(..., "true", "true") => persistent=true, system=true
(..., "true") => system=true

Looking at the code (.../src/libs/installer/environmentvariablesoperation.cpp), the persistent flag is always taken as the third argument; so if one needs to specify system, both arguments are required.

Should this be: [persistent [system]] ?

Ref: .../doc/operations.qdoc

            \li EnvironmentVariable
            \li "EnvironmentVariable" \a key \a value [[\a persistent] \a system]