addModToLib :: ModuleName -> CondTree ConfVar [Dependency] Library ->
    CondTree ConfVar [Dependency] Library
addModToLib modName ct@CondNode{condTreeData = lib} =
    ct{condTreeData = lib{exposedModules = modName `inOrderAdd` exposedModules lib}}
addModToLib :: ModuleName -> CondTree ConfVar [Dependency] Library ->
    CondTree ConfVar [Dependency] Library
addModToLib modName ct@CondNode{condTreeData = lib} =
    ct{condTreeData = lib{exposedModules = modName `inOrderAdd` exposedModules lib}}
addModToLib modName ct@CondNode{condTreeData = lib} =
    ct{condTreeData = lib{exposedModules = modName `inOrderAdd` exposedModules lib}}