Class BasicInsertPolicy

be/src/gutil/strings/split.h:1169–1172

Cannot use output iterator here (e.g. std::inserter, std::back_inserter) because some callers use non-standard containers that don't have iterators, only an insert() or push_back() method.

// because some callers use non-standard containers that don't have iterators,
// only an insert() or push_back() method.
struct BasicInsertPolicy {
  template <class C, class V>
  void operator()(C* c, const V& v) const { c->insert(v); }
};

struct BackInsertPolicy {
  template <class C, class V>