[hist] Fix assertion failure (invalid comparator)

[bellenot]

Fix the following error (visible with the /RTC1 flag on Windows)

libHist: Debug Assertion Failed!
Expression: invalid comparator

[pcanal]

If/Since this changes are needed we also need to update the function documentations and enhance the commit message to point/hint to the part of the standard indicating whether the comparators should strict (existing code) or not (this PR).

[bellenot]

If/Since this changes are needed we also need to update the function documentations and enhance the commit message to point/hint to the part of the standard indicating whether the comparators should strict (existing code) or not (this PR).

You mean this: https://en.cppreference.com/w/cpp/named_req/Compare

[pcanal]

You mean this: en.cppreference.com/w/cpp/named_req/Compare

Yes something like that .. except that I am reading it as asking for strict comparison ... For all a, comp(a, a) == false.

[github-actions]

Test Results

    18 files      18 suites   3d 23h 53m 13s ⏱️
 2 664 tests  2 660 ✅ 0 💤 4 ❌
46 234 runs  46 230 ✅ 0 💤 4 ❌

For more details on these failures, see this check.

Results for commit 9f6c498.

♻️ This comment has been updated with latest results.

[bellenot]

You mean this: en.cppreference.com/w/cpp/named_req/Compare

Yes something like that .. except that I am reading it as asking for strict comparison ... For all a, comp(a, a) == false.

Yes, I know, but the original code is from 2003 (see the commit here and was not using std::stable_sort, should I completely rewrite those methods?