private void AddExterns(
ref CompilationUnitSyntax root,
ref NamespaceDeclarationSyntax namespaceToUpdate,
ExternAliasDirectiveSyntax externAliasDirective)
{
if (namespaceToUpdate != null)
{
namespaceToUpdate = namespaceToUpdate.AddExterns(externAliasDirective);
}
else
{
root = root.AddExterns(externAliasDirective);
}
}