Imperfect C++ Practical Solutions for Real-Life Programming

Chapter 20. Shims

Shim: A thin, often tapered piece of material, used to fill gaps, make something level, or adjust something to fit properly.

This entire chapter revolves around one rather important imperfection that C++ shares with pretty much any language you can think of, so I'm going to start with the imperfection itself.

Imperfection: Logically related types in C++ can, and usually do, have incompatible interfaces and operations, rendering a generalized approach to type manipulation sometimes difficult and often impossible.

Needless to say, this is a pretty bold claim, and a serious problem. The concept of shims described here and the broader concept of explicit generalization supported by it have evolved in two separate threads over several ...