Boost C++ Application Development Cookbook - Second Edition

How it works...

The boost::disable_if_c<bool_value>::type metafunction disables the method, if bool_value equals true. It works just like boost::enable_if_c<!bool_value>::type.

A class passed as the second parameter for boost::enable_if_c or boost::disable_if_c is returned via ::type in the case of successful substitution. In other words, boost::enable_if_c<true, T>::type is the same as T.

Let's go through the process_data(i, i, i) case, step by step. We pass an int as T type and the compiler searches for function process_data(int, int, int). Because there is no such function, the next step is to instantiate a template version of process_data. However, there are two template process_data functions. For example, the compiler starts instantiating ...