Lots and lots of places in the code had broken < operators because they
are returning something like:
foo < other.foo or bar < other.bar;
but this breaks both the strict weak ordering requirements that are
required for the "Compare" requirement for things like
std::map/set/priority_queue.
For example:
a = {.foo=1, .bar=3}
b = {.foo=3, .bar=1}
does not have an ordering over a and b (both `a < b` and `b < a` are
satisfied at the same time).
This needs to be instead something like:
foo < other.foo or (foo == other.foo and bar < other.bar)
but that's a bit clunkier, and it is easier to use std::tie for tuple's
built-in < comparison which does the right thing:
std::tie(foo, bar) < std::tie(other.foo, other.bar)
(Initially I noticed this in SockAddr/sockaddr_in6, but upon further
investigation this extends to the major of multi-field `operator<`'s.)
This fixes it by using std::tie (or something similar) everywhere we are
doing multi-field inequalities.
All #ifndef guards on headers have been removed, I think,
in favor of #pragma once
Headers are now included as `#include "filename"` if the included file
resides in the same directory as the file including it, or any
subdirectory therein. Otherwise they are included as
`#include <project/top/dir/relative/path/filename>`
The above does not include system/os headers.
This commit reflects changes to clang-format rules. Unfortunately,
these rule changes create a massive change to the codebase, which
causes an apparent rewrite of git history.
Git blame's --ignore-rev flag can be used to ignore this commit when
attempting to `git blame` some code.
