.. title:: clang-tidy - google-global-names-in-headers

google-global-names-in-headers
==============================

Flag global namespace pollution in header files.
Right now it only triggers on ``using`` declarations and directives.

The check supports these options:
  - `HeaderFileExtensions`: a comma-separated list of filename extensions
    of header files (the filename extensions should not contain "." prefix).
    "h" by default.
    For extension-less header files, using an empty string or leaving an
    empty string between "," if there are other filename extensions.

The relevant style guide section is
https://google.github.io/styleguide/cppguide.html#Namespaces.
