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Document number: N3596

Date: 2013-03-15

Code Reuse in Class Template Specialization

by Peter Gottschling

Excerpt:

The possibility to define specializations of class templates offers an enormous liberty unthinkable in most other languages. Techniques like enable_if would not be possible without this flexibility.

However, in my (personal) experience over 90% of class specializations duplicate over 80% of the implementation. Conversely, the flexibility praised before is only used in few template classes and paid by code duplications in many classes. We propose a simple extension that provides full
backward compatibility and avoids a lot of duplications.