*
     * ```kt
     * fun usage(action: String.(Int) -> String) {
     *   "hello".<expr>action</expr>(10)
     * }
     * ```
     *
     * The user might want to know the type of the `action` callback. If we always return null for the named references,

            // KtContainerNode are containers used in `KtIfExpressions`, and should be regarded
            // as parentheses for the purpose of this analysis.
            is KtContainerNode ->
                // !!!!CAUTION!!!! Not `parentUse(parent.parent, _parent_)`
                // Here we assume the parent (e.g. If condition) statement
                // ignores the ContainerNode when accessing child