[clnhlzmn]

I think the c++ version could be more understandable but it’s as if the authors intentionally made it as obtuse as possible.

[bregma]

The authors are required to make it obtuse. They're required to use warts on all of the names because most of the code is in the head files and is generative code compiled by users of the library rather than the vendor. In order to avoid naming conflicts they can only use obscured names in their implementation of any but the defined API (eg. naming any internal functions, macros, or variables with leading underscores).

So, the authors did intentionally make it as obtuse as possible for your benefit. It's written to be used, not studied, by all kinds of developers in all kinds of circumstances.

[gosub100]

They could supply a "pretty" version for people who want to review it. Every time I have to step through code (and accidentally step into STL code) it looks sloppy and gross, like a swamp. No comments or organization. I would expect something neatly formatted, and comments saying "This is overload-4 of std::copy()..." etc.