1 files changed, 147 insertions, 0 deletions
diff --git a/include/frozen/string.h b/include/frozen/string.h
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+++ b/include/frozen/string.h
@@ -0,0 +1,147 @@
+/*
+ * Frozen
+ * Copyright 2016 QuarksLab
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#ifndef FROZEN_LETITGO_STRING_H
+#define FROZEN_LETITGO_STRING_H
+
+#include "frozen/bits/elsa.h"
+#include "frozen/bits/hash_string.h"
+#include "frozen/bits/version.h"
+#include "frozen/bits/defines.h"
+
+#include <functional>
+
+#ifdef FROZEN_LETITGO_HAS_STRING_VIEW
+#include <string_view>
+#endif
+
+namespace frozen {
+
+template <typename _CharT>
+class basic_string {
+  using chr_t = _CharT;
+
+  chr_t const *data_;
+  std::size_t size_;
+
+public:
+  template <std::size_t N>
+  constexpr basic_string(chr_t const (&data)[N])
+      : data_(data), size_(N - 1) {}
+  constexpr basic_string(chr_t const *data, std::size_t size)
+      : data_(data), size_(size) {}
+
+#ifdef FROZEN_LETITGO_HAS_STRING_VIEW
+  constexpr basic_string(std::basic_string_view<chr_t> data)
+      : data_(data.data()), size_(data.size()) {}
+#endif
+
+  constexpr basic_string(const basic_string &) noexcept = default;
+  constexpr basic_string &operator=(const basic_string &) noexcept = default;
+
+  constexpr std::size_t size() const { return size_; }
+
+  constexpr chr_t operator[](std::size_t i) const { return data_[i]; }
+
+  constexpr bool operator==(basic_string other) const {
+    if (size_ != other.size_)
+      return false;
+    for (std::size_t i = 0; i < size_; ++i)
+      if (data_[i] != other.data_[i])
+        return false;
+    return true;
+  }
+
+  constexpr bool operator<(const basic_string &other) const {
+    unsigned i = 0;
+    while (i < size() && i < other.size()) {
+      if ((*this)[i] < other[i]) {
+        return true;
+      }
+      if ((*this)[i] > other[i]) {
+        return false;
+      }
+      ++i;
+    }
+    return size() < other.size();
+  }
+
+  constexpr const chr_t *data() const { return data_; }
+  constexpr const chr_t *begin() const { return data(); }
+  constexpr const chr_t *end() const { return data() + size(); }
+};
+
+template <typename _CharT> struct elsa<basic_string<_CharT>> {
+  constexpr std::size_t operator()(basic_string<_CharT> value) const {
+    return hash_string(value);
+  }
+  constexpr std::size_t operator()(basic_string<_CharT> value, std::size_t seed) const {
+    return hash_string(value, seed);
+  }
+};
+
+using string = basic_string<char>;
+using wstring = basic_string<wchar_t>;
+using u16string = basic_string<char16_t>;
+using u32string = basic_string<char32_t>;
+
+#ifdef FROZEN_LETITGO_HAS_CHAR8T
+using u8string = basic_string<char8_t>;
+#endif
+
+namespace string_literals {
+
+constexpr string operator"" _s(const char *data, std::size_t size) {
+  return {data, size};
+}
+
+constexpr wstring operator"" _s(const wchar_t *data, std::size_t size) {
+  return {data, size};
+}
+
+constexpr u16string operator"" _s(const char16_t *data, std::size_t size) {
+  return {data, size};
+}
+
+constexpr u32string operator"" _s(const char32_t *data, std::size_t size) {
+  return {data, size};
+}
+
+#ifdef FROZEN_LETITGO_HAS_CHAR8T
+constexpr u8string operator"" _s(const char8_t *data, std::size_t size) {
+  return {data, size};
+}
+#endif
+
+} // namespace string_literals
+
+} // namespace frozen
+
+namespace std {
+template <typename _CharT> struct hash<frozen::basic_string<_CharT>> {
+  size_t operator()(frozen::basic_string<_CharT> s) const {
+    return frozen::elsa<frozen::basic_string<_CharT>>{}(s);
+  }
+};
+} // namespace std
+
+#endif