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How to Use Class Template Argument Deduction

by Stephan T. Lavavej

From the article:

Class Template Argument Deduction (CTAD) is a C++17 Core Language feature that reduces code verbosity. C++17’s Standard Library also supports CTAD, so after upgrading your toolset, you can take advantage of this new feature when using STL types like std::pair and std::vector. Class templates in other libraries and your own code will partially benefit from CTAD automatically, but sometimes they’ll need a bit of new code (deduction guides) to fully benefit. Fortunately, both using CTAD and providing deduction guides is pretty easy, despite template metaprogramming’s fearsome reputation!