# Extra Clang Tools 21.1.6 documentation

## clang-tidy - google-build-using-namespace

# google-build-using-namespace

Finds `using namespace` directives.

The check implements the following rule of the Google C++ Style Guide:

> You may not use a using-directive to make all names from a namespace available.

    // Forbidden -- This pollutes the namespace.
    using namespace foo;

Corresponding cpplint.py check name: build/namespaces.