https://github.com/anthonywilliams/ccia_code_samples/blob/6e7ae1d66dbd2e8f1ad18a5cf5c6d25a37b92388/listings/listing_9.2.cpp#L51 std::result_of depricated, use std::invoke_result unstead
ccia_code_samples/listings/listing_9.2.cpp
Line 51 in 6e7ae1d
std::result_of depricated, use std::invoke_result unstead