Boost C++ Libraries of the most highly regarded and expertly designed C++ library projects in the world. Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

This is the documentation for an old version of Boost. Click here to view this page for the latest version.

Struct template same_type



// In header: <boost/type_erasure/same_type.hpp>

template<typename T, typename U> 
struct same_type {


A built in concept that indicates that two types are the same. Either T or U or both can be placeholders.

[Warning] Warning

Any number of instances of deduced can be connected with same_type, but there should be at most one regular placeholder in the group. same_type<_a, _b> is not allowed. The reason for this is that the library needs to normalize all the placeholders, and in this context there is no way to decide whether to use _a or _b.