Compile time quick-sort in idiomatic modern C++

A walkthrough of implementing compile-time quicksort in modern C++14 using idiomatic techniques. Covers representing integer sequences with std::integer_sequence, building a concat template to merge sequences, implementing a partition template with unary predicates, and assembling the full recursive quicksort. The implementation is compared favorably to a 2011 version, highlighting how alias templates (concat_t, quicksort_t) and std::conditional_t reduce verbosity and improve readability. A note on pivot selection and O(n²) worst-case behavior is included.