regex/unique_array.go

package main

// Unique array data structure
type uniq_arr[T comparable] struct {
	backingMap map[T]struct{} // Map is used to check if element exists - Empty structs occupy zero memory
	vals       []T
}

func new_uniq_arr[T comparable]() uniq_arr[T] {
	return uniq_arr[T]{
		make(map[T]struct{}),
		make([]T, 0),
	}
}
func (s *uniq_arr[T]) add(vals ...T) {
	for _, item := range vals {
		if !s.contains(item) {
			s.backingMap[item] = struct{}{}
			s.vals = append(s.vals, item)
		}
	}
	return
}

func (s *uniq_arr[T]) contains(val T) bool {
	_, ok := s.backingMap[val]
	return ok
}