2022
https://www.reddit.com/r/cpp/comments/wgtdt7/building_stdvariant_from_scratch_part_1/
    https://github.com/very-cool-name/blog-from-scratch/blob/master/part_i.md
CppCon - Embracing (and also Destroying) Variant Types Safely - Andrei Alexandrescu 0:00 of 1:01:19
    https://www.youtube.com/watch?v=va9I2qivBOA
2020
https://www.bfilipek.com/2020/04/variant-virtual-polymorphism.html
    https://habr.com/ru/company/otus/blog/546158/
2019
https://speakerdeck.com/rollbear/stockholmcpp23-variant-visitation-variations
    https://www.youtube.com/watch?v=ERHYJy5KxQo
Nevin - The many variants of std::variant
    https://www.youtube.com/watch?v=JUxhwf7gYLg
https://mpark.github.io/programming/2019/01/22/variant-visitation-v2/
2018
Wuttke - std variant and the power of pattern matching
    https://github.com/lethal-guitar/VariantTalk
    https://github.com/lethal-guitar/VariantTalk/blob/master/slides/PatternMatching.pdf
    https://www.youtube.com/watch?v=CELWr9roNno
C++ Weekly - Ep 134 - The Best Possible Way To Create A Visitor
https://www.youtube.com/watch?v=EsUmnLgz8QY
https://www.bfilipek.com/2018/09/visit-variants.html
https://pabloariasal.github.io/2018/06/26/std-variant/
https://www.bfilipek.com/2018/06/variant.html
https://arne-mertz.de/2018/05/overload-build-a-variant-visitor-on-the-fly/
https://arne-mertz.de/2018/05/modern-c-features-stdvariant-and-stdvisit/
2017
https://bitbashing.io/std-visit.html
    https://habr.com/post/415737/

samples
https://github.com/Liorst4/cpp-result
https://github.com/codeinred/recursive-variant