- //===- StringSet.h - An efficient set built on StringMap --------*- C++ -*-===// 
- // 
- // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 
- // See https://llvm.org/LICENSE.txt for license information. 
- // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 
- // 
- //===----------------------------------------------------------------------===// 
- /// 
- /// \file 
- ///  StringSet - A set-like wrapper for the StringMap. 
- /// 
- //===----------------------------------------------------------------------===// 
-   
- #ifndef LLVM_ADT_STRINGSET_H 
- #define LLVM_ADT_STRINGSET_H 
-   
- #include "llvm/ADT/StringMap.h" 
-   
- namespace llvm { 
-   
- /// StringSet - A wrapper for StringMap that provides set-like functionality. 
- template <class AllocatorTy = MallocAllocator> 
- class StringSet : public StringMap<std::nullopt_t, AllocatorTy> { 
-   using Base = StringMap<std::nullopt_t, AllocatorTy>; 
-   
- public: 
-   StringSet() = default; 
-   StringSet(std::initializer_list<StringRef> initializer) { 
-     for (StringRef str : initializer) 
-       insert(str); 
-   } 
-   explicit StringSet(AllocatorTy a) : Base(a) {} 
-   
-   std::pair<typename Base::iterator, bool> insert(StringRef key) { 
-     return Base::try_emplace(key); 
-   } 
-   
-   template <typename InputIt> 
-   void insert(InputIt begin, InputIt end) { 
-     for (auto it = begin; it != end; ++it) 
-       insert(*it); 
-   } 
-   
-   template <typename ValueTy> 
-   std::pair<typename Base::iterator, bool> 
-   insert(const StringMapEntry<ValueTy> &mapEntry) { 
-     return insert(mapEntry.getKey()); 
-   } 
-   
-   /// Check if the set contains the given \c key. 
-   bool contains(StringRef key) const { return Base::FindKey(key) != -1; } 
- }; 
-   
- } // end namespace llvm 
-   
- #endif // LLVM_ADT_STRINGSET_H 
-