UFile (package = )
    UClass (name = PropertyReferencesKt)
        UMethod (name = properties)
            [!] UnknownKotlinExpression (BLOCK)
        UMethod (name = ext)
            UParameter (name = $this$ext)
            [!] UnknownKotlinExpression (BLOCK)
    UClass (name = A)
        UField (name = privateProp)
            [!] UnknownKotlinExpression (INTEGER_CONSTANT)
        UField (name = mutableProp)
        UMethod (name = A)
            UParameter (name = init)
        UMethod (name = getMutableProp)
        UMethod (name = setMutableProp)
            UParameter (name = value)
        UMethod (name = add)
            UParameter (name = x)
            [!] UnknownKotlinExpression (BLOCK)
