The Design and Evolution of C++, First Edition

17. Namespaces

Always design a thing by considering it in its next larger context.

– Eliel Saarinen

Global scope problems — ideals for a solution — namespaces, using-declarations, and using-directives — how to use namespaces — name-spaces and classes — C compatibility.

17.1 Introduction

C provides a single global namespace for all names that don’t conveniently fit into a single function, a single struct, or a single translation unit. This causes problems with name clashes. I first grappled with this problem in the original design of C++ by defaulting all names to be local to a translation unit and requiring an explicit extern declaration to make them visible to other translation units. As described in §3.12, this idea was neither sufficient ...