Inferrence isn't magic and has sensible limits. To quote: > Of course, this requires the function body to be visible. https://isocpp.org/wiki/faq/cpp14-langu

Inferrence isn't magic and has sensible limits. To quote: > Of course, this requires the function body to be visible. https://isocpp.org/wiki/faq/cpp14-language#generalized-return https://isocpp.org/wiki/faq/cpp14-language#generalized-retur...