llvm/llvm/include/llvm/ADT/StringRef.h

//===- StringRef.h - Constant String Reference Wrapper ----------*- 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
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_ADT_STRINGREF_H
#define LLVM_ADT_STRINGREF_H

#include "llvm/ADT/DenseMapInfo.h"
#include "llvm/ADT/STLFunctionalExtras.h"
#include "llvm/ADT/iterator_range.h"
#include "llvm/Support/Compiler.h"
#include <algorithm>
#include <cassert>
#include <cstddef>
#include <cstring>
#include <iterator>
#include <limits>
#include <string>
#include <string_view>
#include <type_traits>
#include <utility>

namespace llvm {

  class APInt;
  class hash_code;
  template <typename T> class SmallVectorImpl;
  class StringRef;

  /// Helper functions for StringRef::getAsInteger.
  bool getAsUnsignedInteger(StringRef Str, unsigned Radix,
                            unsigned long long &Result);

  bool getAsSignedInteger(StringRef Str, unsigned Radix, long long &Result);

  bool consumeUnsignedInteger(StringRef &Str, unsigned Radix,
                              unsigned long long &Result);
  bool consumeSignedInteger(StringRef &Str, unsigned Radix, long long &Result);

  /// StringRef - Represent a constant reference to a string, i.e. a character
  /// array and a length, which need not be null terminated.
  ///
  /// This class does not own the string data, it is expected to be used in
  /// situations where the character data resides in some other buffer, whose
  /// lifetime extends past that of the StringRef. For this reason, it is not in
  /// general safe to store a StringRef.
  class LLVM_GSL_POINTER StringRef { … };

  /// A wrapper around a string literal that serves as a proxy for constructing
  /// global tables of StringRefs with the length computed at compile time.
  /// In order to avoid the invocation of a global constructor, StringLiteral
  /// should *only* be used in a constexpr context, as such:
  ///
  /// constexpr StringLiteral S("test");
  ///
  class StringLiteral : public StringRef { … };

  /// @name StringRef Comparison Operators
  /// @{

  inline bool operator==(StringRef LHS, StringRef RHS) { … }

  inline bool operator!=(StringRef LHS, StringRef RHS) { … }

  inline bool operator<(StringRef LHS, StringRef RHS) { … }

  inline bool operator<=(StringRef LHS, StringRef RHS) { … }

  inline bool operator>(StringRef LHS, StringRef RHS) { … }

  inline bool operator>=(StringRef LHS, StringRef RHS) { … }

  inline std::string &operator+=(std::string &buffer, StringRef string) { … }

  /// @}

  /// Compute a hash_code for a StringRef.
  [[nodiscard]] hash_code hash_value(StringRef S);

  // Provide DenseMapInfo for StringRefs.
  template <> struct DenseMapInfo<StringRef, void> { … };

} // end namespace llvm

#endif // LLVM_ADT_STRINGREF_H