15 // The Flags class provides a type-safe way of storing OR-combinations of enum
16 // values. The Flags<T, S> class is a template class, where T is an enum type,
25 class Flags final {
30   Flags() : mask_(0) {}  in Flags()  function
31   Flags(flag_type flag)  // NOLINT(runtime/explicit)  in Flags()  function
33   explicit Flags(mask_type mask) : mask_(static_cast<S>(mask)) {}  in Flags()  function
42   Flags& operator&=(const Flags& flags) {
43     mask_ &= flags.mask_;
46   Flags& operator|=(const Flags& flags) {
47     mask_ |= flags.mask_;
50   Flags& operator^=(const Flags& flags) {
51     mask_ ^= flags.mask_;
55   Flags operator&(const Flags& flags) const { return Flags(*this) &= flags; }
56   Flags operator|(const Flags& flags) const { return Flags(*this) |= flags; }
57   Flags operator^(const Flags& flags) const { return Flags(*this) ^= flags; }
59   Flags& operator&=(flag_type flag) { return operator&=(Flags(flag)); }
60   Flags& operator|=(flag_type flag) { return operator|=(Flags(flag)); }
61   Flags& operator^=(flag_type flag) { return operator^=(Flags(flag)); }
63   Flags operator&(flag_type flag) const { return operator&(Flags(flag)); }
64   Flags operator|(flag_type flag) const { return operator|(Flags(flag)); }
65   Flags operator^(flag_type flag) const { return operator^(Flags(flag)); }
67   Flags operator~() const { return Flags(~mask_); }
72   friend size_t hash_value(const Flags& flags) { return flags.mask_; }  in hash_value()  argument