C++ Primer, Fifth Edition

Name Lookup in Nested Class Scope

Normal rules apply for name lookup (§ 7.4.1, p. 283) inside a nested class. Of course, because a nested class is a nested scope, the nested class has additional enclosing class scopes to search. This nesting of scopes explains why we didn’t define line_no inside the nested version of QueryResult. Our original QueryResult class defined this member so that its own members could avoid having to write TextQuery::line_no. Having nested the definition of our results class inside TextQuery, we no longer need this typedef. The nested QueryResult class can access line_no without specifying that line_no is defined in TextQuery.

As we’ve seen, a nested class is a type member of its enclosing class. Members of the enclosing ...