diff --git a/README.md b/README.md
index 2076ace..15f4030 100644
--- a/README.md
+++ b/README.md
@@ -382,7 +382,7 @@
 
 ## Supported compilers
 
-Inja uses `string_view` from C++17, but includes the [polyfill](https://github.com/martinmoene/string-view-lite) from martinmoene. This way, the minimum version is C++11. Currently, the following compilers are tested:
+Inja uses the `string_view` feature of the C++17 STL. Currently, the following compilers are tested:
 
 - GCC 7 - 11 (and possibly later)
 - Clang 4 - 12 (and possibly later)
diff --git a/include/inja/config.hpp b/include/inja/config.hpp
index b520721..0a8f9b7 100644
--- a/include/inja/config.hpp
+++ b/include/inja/config.hpp
@@ -4,7 +4,6 @@
 #include <functional>
 #include <string>
 
-#include "string_view.hpp"
 #include "template.hpp"
 
 namespace inja {
diff --git a/include/inja/environment.hpp b/include/inja/environment.hpp
index 0b948ce..e102046 100644
--- a/include/inja/environment.hpp
+++ b/include/inja/environment.hpp
@@ -6,12 +6,12 @@
 #include <memory>
 #include <sstream>
 #include <string>
+#include <string_view>
 
 #include "config.hpp"
 #include "function_storage.hpp"
 #include "parser.hpp"
 #include "renderer.hpp"
-#include "string_view.hpp"
 #include "template.hpp"
 #include "utils.hpp"
 
@@ -93,7 +93,7 @@
     render_config.throw_at_missing_includes = will_throw;
   }
 
-  Template parse(nonstd::string_view input) {
+  Template parse(std::string_view input) {
     Parser parser(parser_config, lexer_config, template_storage, function_storage);
     return parser.parse(input);
   }
@@ -109,7 +109,7 @@
     return parse_template(filename);
   }
 
-  std::string render(nonstd::string_view input, const json &data) { return render(parse(input), data); }
+  std::string render(std::string_view input, const json &data) { return render(parse(input), data); }
 
   std::string render(const Template &tmpl, const json &data) {
     std::stringstream os;
@@ -217,14 +217,14 @@
 /*!
 @brief render with default settings to a string
 */
-inline std::string render(nonstd::string_view input, const json &data) {
+inline std::string render(std::string_view input, const json &data) {
   return Environment().render(input, data);
 }
 
 /*!
 @brief render with default settings to the given output stream
 */
-inline void render_to(std::ostream &os, nonstd::string_view input, const json &data) {
+inline void render_to(std::ostream &os, std::string_view input, const json &data) {
   Environment env;
   env.render_to(os, env.parse(input), data);
 }
diff --git a/include/inja/function_storage.hpp b/include/inja/function_storage.hpp
index 1e30a0f..90c3955 100644
--- a/include/inja/function_storage.hpp
+++ b/include/inja/function_storage.hpp
@@ -1,9 +1,9 @@
 #ifndef INCLUDE_INJA_FUNCTION_STORAGE_HPP_
 #define INCLUDE_INJA_FUNCTION_STORAGE_HPP_
 
+#include <string_view>
 #include <vector>
 
-#include "string_view.hpp"
 
 namespace inja {
 
@@ -110,15 +110,15 @@
   };
 
 public:
-  void add_builtin(nonstd::string_view name, int num_args, Operation op) {
+  void add_builtin(std::string_view name, int num_args, Operation op) {
     function_storage.emplace(std::make_pair(static_cast<std::string>(name), num_args), FunctionData { op });
   }
 
-  void add_callback(nonstd::string_view name, int num_args, const CallbackFunction &callback) {
+  void add_callback(std::string_view name, int num_args, const CallbackFunction &callback) {
     function_storage.emplace(std::make_pair(static_cast<std::string>(name), num_args), FunctionData { Operation::Callback, callback });
   }
 
-  FunctionData find_function(nonstd::string_view name, int num_args) const {
+  FunctionData find_function(std::string_view name, int num_args) const {
     auto it = function_storage.find(std::make_pair(static_cast<std::string>(name), num_args));
     if (it != function_storage.end()) {
       return it->second;
diff --git a/include/inja/inja.hpp b/include/inja/inja.hpp
index f6d3d6e..1434f57 100644
--- a/include/inja/inja.hpp
+++ b/include/inja/inja.hpp
@@ -53,7 +53,6 @@
 #include "exceptions.hpp"
 #include "parser.hpp"
 #include "renderer.hpp"
-#include "string_view.hpp"
 #include "template.hpp"
 
 #endif // INCLUDE_INJA_INJA_HPP_
diff --git a/include/inja/lexer.hpp b/include/inja/lexer.hpp
index 58768e4..7bcbf56 100644
--- a/include/inja/lexer.hpp
+++ b/include/inja/lexer.hpp
@@ -39,12 +39,12 @@
 
   State state;
   MinusState minus_state;
-  nonstd::string_view m_in;
+  std::string_view m_in;
   size_t tok_start;
   size_t pos;
 
 
-  Token scan_body(nonstd::string_view close, Token::Kind closeKind, nonstd::string_view close_trim = nonstd::string_view(), bool trim = false) {
+  Token scan_body(std::string_view close, Token::Kind closeKind, std::string_view close_trim = std::string_view(), bool trim = false) {
   again:
     // skip whitespace (except for \n as it might be a close)
     if (tok_start >= m_in.size()) {
@@ -254,8 +254,8 @@
     }
   }
 
-  static nonstd::string_view clear_final_line_if_whitespace(nonstd::string_view text) {
-    nonstd::string_view result = text;
+  static std::string_view clear_final_line_if_whitespace(std::string_view text) {
+    std::string_view result = text;
     while (!result.empty()) {
       const char ch = result.back();
       if (ch == ' ' || ch == '\t') {
@@ -276,7 +276,7 @@
     return get_source_location(m_in, tok_start);
   }
 
-  void start(nonstd::string_view input) {
+  void start(std::string_view input) {
     m_in = input;
     tok_start = 0;
     pos = 0;
@@ -302,7 +302,7 @@
     case State::Text: {
       // fast-scan to first open character
       const size_t open_start = m_in.substr(pos).find_first_of(config.open_chars);
-      if (open_start == nonstd::string_view::npos) {
+      if (open_start == std::string_view::npos) {
         // didn't find open, return remaining text as text token
         pos = m_in.size();
         return make_token(Token::Kind::Text);
@@ -310,7 +310,7 @@
       pos += open_start;
 
       // try to match one of the opening sequences, and get the close
-      nonstd::string_view open_str = m_in.substr(pos);
+      std::string_view open_str = m_in.substr(pos);
       bool must_lstrip = false;
       if (inja::string_view::starts_with(open_str, config.expression_open)) {
         if (inja::string_view::starts_with(open_str, config.expression_open_force_lstrip)) {
@@ -344,7 +344,7 @@
         goto again;
       }
 
-      nonstd::string_view text = string_view::slice(m_in, tok_start, pos);
+      std::string_view text = string_view::slice(m_in, tok_start, pos);
       if (must_lstrip) {
         text = clear_final_line_if_whitespace(text);
       }
@@ -403,7 +403,7 @@
     case State::CommentBody: {
       // fast-scan to comment close
       const size_t end = m_in.substr(pos).find(config.comment_close);
-      if (end == nonstd::string_view::npos) {
+      if (end == std::string_view::npos) {
         pos = m_in.size();
         return make_token(Token::Kind::Eof);
       }
diff --git a/include/inja/node.hpp b/include/inja/node.hpp
index fd26abd..def2310 100644
--- a/include/inja/node.hpp
+++ b/include/inja/node.hpp
@@ -2,10 +2,10 @@
 #define INCLUDE_INJA_NODE_HPP_
 
 #include <string>
+#include <string_view>
 #include <utility>
 
 #include "function_storage.hpp"
-#include "string_view.hpp"
 #include "utils.hpp"
 
 
@@ -113,10 +113,10 @@
   const std::string name;
   const json::json_pointer ptr;
 
-  static std::string convert_dot_to_json_ptr(nonstd::string_view ptr_name) {
+  static std::string convert_dot_to_json_ptr(std::string_view ptr_name) {
     std::string result;
     do {
-      nonstd::string_view part;
+      std::string_view part;
       std::tie(part, ptr_name) = string_view::split(ptr_name, '.');
       result.push_back('/');
       result.append(part.begin(), part.end());
@@ -124,7 +124,7 @@
     return result;
   }
 
-  explicit JsonNode(nonstd::string_view ptr_name, size_t pos) : ExpressionNode(pos), name(ptr_name), ptr(json::json_pointer(convert_dot_to_json_ptr(ptr_name))) { }
+  explicit JsonNode(std::string_view ptr_name, size_t pos) : ExpressionNode(pos), name(ptr_name), ptr(json::json_pointer(convert_dot_to_json_ptr(ptr_name))) { }
 
   void accept(NodeVisitor& v) const {
     v.visit(*this);
@@ -150,7 +150,7 @@
   std::vector<std::shared_ptr<ExpressionNode>> arguments;
   CallbackFunction callback;
 
-  explicit FunctionNode(nonstd::string_view name, size_t pos) : ExpressionNode(pos), precedence(8), associativity(Associativity::Left), operation(Op::Callback), name(name), number_args(1) { }
+  explicit FunctionNode(std::string_view name, size_t pos) : ExpressionNode(pos), precedence(8), associativity(Associativity::Left), operation(Op::Callback), name(name), number_args(1) { }
   explicit FunctionNode(Op operation, size_t pos) : ExpressionNode(pos), operation(operation), number_args(1) {
     switch (operation) {
       case Op::Not: {
diff --git a/include/inja/parser.hpp b/include/inja/parser.hpp
index ed8dbe5..f22370e 100644
--- a/include/inja/parser.hpp
+++ b/include/inja/parser.hpp
@@ -37,7 +37,7 @@
   size_t current_bracket_level {0};
   size_t current_brace_level {0};
 
-  nonstd::string_view json_literal_start;
+  std::string_view json_literal_start;
 
   BlockNode *current_block {nullptr};
   ExpressionListNode *current_expression_list {nullptr};
@@ -70,7 +70,7 @@
   }
 
   inline void add_json_literal(const char* content_ptr) {
-    nonstd::string_view json_text(json_literal_start.data(), tok.text.data() - json_literal_start.data() + tok.text.size());
+    std::string_view json_text(json_literal_start.data(), tok.text.data() - json_literal_start.data() + tok.text.size());
     arguments.emplace_back(std::make_shared<LiteralNode>(json::parse(json_text), json_text.data() - content_ptr));
   }
 
@@ -85,7 +85,7 @@
     arguments.emplace_back(function);
   }
 
-  void add_to_template_storage(nonstd::string_view path, std::string& template_name) {
+  void add_to_template_storage(std::string_view path, std::string& template_name) {
     if (template_storage.find(template_name) != template_storage.end()) {
       return;
     }
@@ -366,7 +366,7 @@
     return true;
   }
 
-  bool parse_statement(Template &tmpl, Token::Kind closing, nonstd::string_view path) {
+  bool parse_statement(Template &tmpl, Token::Kind closing, std::string_view path) {
     if (tok.kind != Token::Kind::Id) {
       return false;
     }
@@ -568,7 +568,7 @@
     return true;
   }
 
-  void parse_into(Template &tmpl, nonstd::string_view path) {
+  void parse_into(Template &tmpl, std::string_view path) {
     lexer.start(tmpl.content);
     current_block = &tmpl.root;
 
@@ -638,18 +638,18 @@
                   TemplateStorage &template_storage, const FunctionStorage &function_storage)
       : config(parser_config), lexer(lexer_config), template_storage(template_storage), function_storage(function_storage) { }
 
-  Template parse(nonstd::string_view input, nonstd::string_view path) {
+  Template parse(std::string_view input, std::string_view path) {
     auto result = Template(static_cast<std::string>(input));
     parse_into(result, path);
     return result;
   }
 
-  Template parse(nonstd::string_view input) {
+  Template parse(std::string_view input) {
     return parse(input, "./");
   }
 
-  void parse_into_template(Template& tmpl, nonstd::string_view filename) {
-    nonstd::string_view path = filename.substr(0, filename.find_last_of("/\\") + 1);
+  void parse_into_template(Template& tmpl, std::string_view filename) {
+    std::string_view path = filename.substr(0, filename.find_last_of("/\\") + 1);
 
     // StringRef path = sys::path::parent_path(filename);
     auto sub_parser = Parser(config, lexer.get_config(), template_storage, function_storage);
diff --git a/include/inja/string_view.hpp b/include/inja/string_view.hpp
deleted file mode 100644
index 2bb50c9..0000000
--- a/include/inja/string_view.hpp
+++ /dev/null
@@ -1,1416 +0,0 @@
-// Copyright 2017-2019 by Martin Moene
-//
-// string-view lite, a C++17-like string_view for C++98 and later.
-// For more information see https://github.com/martinmoene/string-view-lite
-//
-// Distributed under the Boost Software License, Version 1.0.
-// (See accompanying file LICENSE.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-
-#pragma once
-
-#ifndef NONSTD_SV_LITE_H_INCLUDED
-#define NONSTD_SV_LITE_H_INCLUDED
-
-#define string_view_lite_MAJOR 1
-#define string_view_lite_MINOR 4
-#define string_view_lite_PATCH 0
-
-#define string_view_lite_VERSION                                                                                       \
-  nssv_STRINGIFY(string_view_lite_MAJOR) "." nssv_STRINGIFY(string_view_lite_MINOR) "." nssv_STRINGIFY(                \
-      string_view_lite_PATCH)
-
-#define nssv_STRINGIFY(x) nssv_STRINGIFY_(x)
-#define nssv_STRINGIFY_(x) #x
-
-// string-view lite configuration:
-
-#define nssv_STRING_VIEW_DEFAULT 0
-#define nssv_STRING_VIEW_NONSTD 1
-#define nssv_STRING_VIEW_STD 2
-
-#if !defined(nssv_CONFIG_SELECT_STRING_VIEW)
-#define nssv_CONFIG_SELECT_STRING_VIEW (nssv_HAVE_STD_STRING_VIEW ? nssv_STRING_VIEW_STD : nssv_STRING_VIEW_NONSTD)
-#endif
-
-#if defined(nssv_CONFIG_SELECT_STD_STRING_VIEW) || defined(nssv_CONFIG_SELECT_NONSTD_STRING_VIEW)
-#error nssv_CONFIG_SELECT_STD_STRING_VIEW and nssv_CONFIG_SELECT_NONSTD_STRING_VIEW are deprecated and removed, please use nssv_CONFIG_SELECT_STRING_VIEW=nssv_STRING_VIEW_...
-#endif
-
-#ifndef nssv_CONFIG_STD_SV_OPERATOR
-#define nssv_CONFIG_STD_SV_OPERATOR 0
-#endif
-
-#ifndef nssv_CONFIG_USR_SV_OPERATOR
-#define nssv_CONFIG_USR_SV_OPERATOR 1
-#endif
-
-#ifdef nssv_CONFIG_CONVERSION_STD_STRING
-#define nssv_CONFIG_CONVERSION_STD_STRING_CLASS_METHODS nssv_CONFIG_CONVERSION_STD_STRING
-#define nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS nssv_CONFIG_CONVERSION_STD_STRING
-#endif
-
-#ifndef nssv_CONFIG_CONVERSION_STD_STRING_CLASS_METHODS
-#define nssv_CONFIG_CONVERSION_STD_STRING_CLASS_METHODS 1
-#endif
-
-#ifndef nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS
-#define nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS 1
-#endif
-
-// Control presence of exception handling (try and auto discover):
-
-#ifndef nssv_CONFIG_NO_EXCEPTIONS
-#if defined(__cpp_exceptions) || defined(__EXCEPTIONS) || defined(_CPPUNWIND)
-#define nssv_CONFIG_NO_EXCEPTIONS 0
-#else
-#define nssv_CONFIG_NO_EXCEPTIONS 1
-#endif
-#endif
-
-// C++ language version detection (C++20 is speculative):
-// Note: VC14.0/1900 (VS2015) lacks too much from C++14.
-
-#ifndef nssv_CPLUSPLUS
-#if defined(_MSVC_LANG) && !defined(__clang__)
-#define nssv_CPLUSPLUS (_MSC_VER == 1900 ? 201103L : _MSVC_LANG)
-#else
-#define nssv_CPLUSPLUS __cplusplus
-#endif
-#endif
-
-#define nssv_CPP98_OR_GREATER (nssv_CPLUSPLUS >= 199711L)
-#define nssv_CPP11_OR_GREATER (nssv_CPLUSPLUS >= 201103L)
-#define nssv_CPP11_OR_GREATER_ (nssv_CPLUSPLUS >= 201103L)
-#define nssv_CPP14_OR_GREATER (nssv_CPLUSPLUS >= 201402L)
-#define nssv_CPP17_OR_GREATER (nssv_CPLUSPLUS >= 201703L)
-#define nssv_CPP20_OR_GREATER (nssv_CPLUSPLUS >= 202000L)
-
-// use C++17 std::string_view if available and requested:
-
-#if nssv_CPP17_OR_GREATER && defined(__has_include)
-#if __has_include(<string_view> )
-#define nssv_HAVE_STD_STRING_VIEW 1
-#else
-#define nssv_HAVE_STD_STRING_VIEW 0
-#endif
-#else
-#define nssv_HAVE_STD_STRING_VIEW 0
-#endif
-
-#define nssv_USES_STD_STRING_VIEW                                                                                      \
-  ((nssv_CONFIG_SELECT_STRING_VIEW == nssv_STRING_VIEW_STD) ||                                                         \
-   ((nssv_CONFIG_SELECT_STRING_VIEW == nssv_STRING_VIEW_DEFAULT) && nssv_HAVE_STD_STRING_VIEW))
-
-#define nssv_HAVE_STARTS_WITH (nssv_CPP20_OR_GREATER || !nssv_USES_STD_STRING_VIEW)
-#define nssv_HAVE_ENDS_WITH nssv_HAVE_STARTS_WITH
-
-//
-// Use C++17 std::string_view:
-//
-
-#if nssv_USES_STD_STRING_VIEW
-
-#include <string_view>
-
-// Extensions for std::string:
-
-#if nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS
-
-namespace nonstd {
-
-template <class CharT, class Traits, class Allocator = std::allocator<CharT>>
-std::basic_string<CharT, Traits, Allocator> to_string(std::basic_string_view<CharT, Traits> v,
-                                                      Allocator const &a = Allocator()) {
-  return std::basic_string<CharT, Traits, Allocator>(v.begin(), v.end(), a);
-}
-
-template <class CharT, class Traits, class Allocator>
-std::basic_string_view<CharT, Traits> to_string_view(std::basic_string<CharT, Traits, Allocator> const &s) {
-  return std::basic_string_view<CharT, Traits>(s.data(), s.size());
-}
-
-// Literal operators sv and _sv:
-
-#if nssv_CONFIG_STD_SV_OPERATOR
-
-using namespace std::literals::string_view_literals;
-
-#endif
-
-#if nssv_CONFIG_USR_SV_OPERATOR
-
-inline namespace literals {
-inline namespace string_view_literals {
-
-constexpr std::string_view operator"" _sv(const char *str, size_t len) noexcept // (1)
-{
-  return std::string_view {str, len};
-}
-
-constexpr std::u16string_view operator"" _sv(const char16_t *str, size_t len) noexcept // (2)
-{
-  return std::u16string_view {str, len};
-}
-
-constexpr std::u32string_view operator"" _sv(const char32_t *str, size_t len) noexcept // (3)
-{
-  return std::u32string_view {str, len};
-}
-
-constexpr std::wstring_view operator"" _sv(const wchar_t *str, size_t len) noexcept // (4)
-{
-  return std::wstring_view {str, len};
-}
-
-} // namespace string_view_literals
-} // namespace literals
-
-#endif // nssv_CONFIG_USR_SV_OPERATOR
-
-} // namespace nonstd
-
-#endif // nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS
-
-namespace nonstd {
-
-using std::basic_string_view;
-using std::string_view;
-using std::u16string_view;
-using std::u32string_view;
-using std::wstring_view;
-
-// literal "sv" and "_sv", see above
-
-using std::operator==;
-using std::operator!=;
-using std::operator<;
-using std::operator<=;
-using std::operator>;
-using std::operator>=;
-
-using std::operator<<;
-
-} // namespace nonstd
-
-#else // nssv_HAVE_STD_STRING_VIEW
-
-//
-// Before C++17: use string_view lite:
-//
-
-// Compiler versions:
-//
-// MSVC++ 6.0  _MSC_VER == 1200 (Visual Studio 6.0)
-// MSVC++ 7.0  _MSC_VER == 1300 (Visual Studio .NET 2002)
-// MSVC++ 7.1  _MSC_VER == 1310 (Visual Studio .NET 2003)
-// MSVC++ 8.0  _MSC_VER == 1400 (Visual Studio 2005)
-// MSVC++ 9.0  _MSC_VER == 1500 (Visual Studio 2008)
-// MSVC++ 10.0 _MSC_VER == 1600 (Visual Studio 2010)
-// MSVC++ 11.0 _MSC_VER == 1700 (Visual Studio 2012)
-// MSVC++ 12.0 _MSC_VER == 1800 (Visual Studio 2013)
-// MSVC++ 14.0 _MSC_VER == 1900 (Visual Studio 2015)
-// MSVC++ 14.1 _MSC_VER >= 1910 (Visual Studio 2017)
-
-#if defined(_MSC_VER) && !defined(__clang__)
-#define nssv_COMPILER_MSVC_VER (_MSC_VER)
-#define nssv_COMPILER_MSVC_VERSION (_MSC_VER / 10 - 10 * (5 + (_MSC_VER < 1900)))
-#else
-#define nssv_COMPILER_MSVC_VER 0
-#define nssv_COMPILER_MSVC_VERSION 0
-#endif
-
-#define nssv_COMPILER_VERSION(major, minor, patch) (10 * (10 * (major) + (minor)) + (patch))
-
-#if defined(__clang__)
-#define nssv_COMPILER_CLANG_VERSION nssv_COMPILER_VERSION(__clang_major__, __clang_minor__, __clang_patchlevel__)
-#else
-#define nssv_COMPILER_CLANG_VERSION 0
-#endif
-
-#if defined(__GNUC__) && !defined(__clang__)
-#define nssv_COMPILER_GNUC_VERSION nssv_COMPILER_VERSION(__GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__)
-#else
-#define nssv_COMPILER_GNUC_VERSION 0
-#endif
-
-// half-open range [lo..hi):
-#define nssv_BETWEEN(v, lo, hi) ((lo) <= (v) && (v) < (hi))
-
-// Presence of language and library features:
-
-#ifdef _HAS_CPP0X
-#define nssv_HAS_CPP0X _HAS_CPP0X
-#else
-#define nssv_HAS_CPP0X 0
-#endif
-
-// Unless defined otherwise below, consider VC14 as C++11 for variant-lite:
-
-#if nssv_COMPILER_MSVC_VER >= 1900
-#undef nssv_CPP11_OR_GREATER
-#define nssv_CPP11_OR_GREATER 1
-#endif
-
-#define nssv_CPP11_90 (nssv_CPP11_OR_GREATER_ || nssv_COMPILER_MSVC_VER >= 1500)
-#define nssv_CPP11_100 (nssv_CPP11_OR_GREATER_ || nssv_COMPILER_MSVC_VER >= 1600)
-#define nssv_CPP11_110 (nssv_CPP11_OR_GREATER_ || nssv_COMPILER_MSVC_VER >= 1700)
-#define nssv_CPP11_120 (nssv_CPP11_OR_GREATER_ || nssv_COMPILER_MSVC_VER >= 1800)
-#define nssv_CPP11_140 (nssv_CPP11_OR_GREATER_ || nssv_COMPILER_MSVC_VER >= 1900)
-#define nssv_CPP11_141 (nssv_CPP11_OR_GREATER_ || nssv_COMPILER_MSVC_VER >= 1910)
-
-#define nssv_CPP14_000 (nssv_CPP14_OR_GREATER)
-#define nssv_CPP17_000 (nssv_CPP17_OR_GREATER)
-
-// Presence of C++11 language features:
-
-#define nssv_HAVE_CONSTEXPR_11 nssv_CPP11_140
-#define nssv_HAVE_EXPLICIT_CONVERSION nssv_CPP11_140
-#define nssv_HAVE_INLINE_NAMESPACE nssv_CPP11_140
-#define nssv_HAVE_NOEXCEPT nssv_CPP11_140
-#define nssv_HAVE_NULLPTR nssv_CPP11_100
-#define nssv_HAVE_REF_QUALIFIER nssv_CPP11_140
-#define nssv_HAVE_UNICODE_LITERALS nssv_CPP11_140
-#define nssv_HAVE_USER_DEFINED_LITERALS nssv_CPP11_140
-#define nssv_HAVE_WCHAR16_T nssv_CPP11_100
-#define nssv_HAVE_WCHAR32_T nssv_CPP11_100
-
-#if !((nssv_CPP11_OR_GREATER && nssv_COMPILER_CLANG_VERSION) || nssv_BETWEEN(nssv_COMPILER_CLANG_VERSION, 300, 400))
-#define nssv_HAVE_STD_DEFINED_LITERALS nssv_CPP11_140
-#else
-#define nssv_HAVE_STD_DEFINED_LITERALS 0
-#endif
-
-// Presence of C++14 language features:
-
-#define nssv_HAVE_CONSTEXPR_14 nssv_CPP14_000
-
-// Presence of C++17 language features:
-
-#define nssv_HAVE_NODISCARD nssv_CPP17_000
-
-// Presence of C++ library features:
-
-#define nssv_HAVE_STD_HASH nssv_CPP11_120
-
-// C++ feature usage:
-
-#if nssv_HAVE_CONSTEXPR_11
-#define nssv_constexpr constexpr
-#else
-#define nssv_constexpr /*constexpr*/
-#endif
-
-#if nssv_HAVE_CONSTEXPR_14
-#define nssv_constexpr14 constexpr
-#else
-#define nssv_constexpr14 /*constexpr*/
-#endif
-
-#if nssv_HAVE_EXPLICIT_CONVERSION
-#define nssv_explicit explicit
-#else
-#define nssv_explicit /*explicit*/
-#endif
-
-#if nssv_HAVE_INLINE_NAMESPACE
-#define nssv_inline_ns inline
-#else
-#define nssv_inline_ns /*inline*/
-#endif
-
-#if nssv_HAVE_NOEXCEPT
-#define nssv_noexcept noexcept
-#else
-#define nssv_noexcept /*noexcept*/
-#endif
-
-//#if nssv_HAVE_REF_QUALIFIER
-//# define nssv_ref_qual  &
-//# define nssv_refref_qual  &&
-//#else
-//# define nssv_ref_qual  /*&*/
-//# define nssv_refref_qual  /*&&*/
-//#endif
-
-#if nssv_HAVE_NULLPTR
-#define nssv_nullptr nullptr
-#else
-#define nssv_nullptr NULL
-#endif
-
-#if nssv_HAVE_NODISCARD
-#define nssv_nodiscard [[nodiscard]]
-#else
-#define nssv_nodiscard /*[[nodiscard]]*/
-#endif
-
-// Additional includes:
-
-#include <algorithm>
-#include <cassert>
-#include <iterator>
-#include <limits>
-#include <ostream>
-#include <string> // std::char_traits<>
-
-#if !nssv_CONFIG_NO_EXCEPTIONS
-#include <stdexcept>
-#endif
-
-#if nssv_CPP11_OR_GREATER
-#include <type_traits>
-#endif
-
-// Clang, GNUC, MSVC warning suppression macros:
-
-#if defined(__clang__)
-#pragma clang diagnostic ignored "-Wreserved-user-defined-literal"
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wuser-defined-literals"
-#elif defined(__GNUC__)
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wliteral-suffix"
-#endif // __clang__
-
-#if nssv_COMPILER_MSVC_VERSION >= 140
-#define nssv_SUPPRESS_MSGSL_WARNING(expr) [[gsl::suppress(expr)]]
-#define nssv_SUPPRESS_MSVC_WARNING(code, descr) __pragma(warning(suppress : code))
-#define nssv_DISABLE_MSVC_WARNINGS(codes) __pragma(warning(push)) __pragma(warning(disable : codes))
-#else
-#define nssv_SUPPRESS_MSGSL_WARNING(expr)
-#define nssv_SUPPRESS_MSVC_WARNING(code, descr)
-#define nssv_DISABLE_MSVC_WARNINGS(codes)
-#endif
-
-#if defined(__clang__)
-#define nssv_RESTORE_WARNINGS() _Pragma("clang diagnostic pop")
-#elif defined(__GNUC__)
-#define nssv_RESTORE_WARNINGS() _Pragma("GCC diagnostic pop")
-#elif nssv_COMPILER_MSVC_VERSION >= 140
-#define nssv_RESTORE_WARNINGS() __pragma(warning(pop))
-#else
-#define nssv_RESTORE_WARNINGS()
-#endif
-
-// Suppress the following MSVC (GSL) warnings:
-// - C4455, non-gsl   : 'operator ""sv': literal suffix identifiers that do not
-//                      start with an underscore are reserved
-// - C26472, gsl::t.1 : don't use a static_cast for arithmetic conversions;
-//                      use brace initialization, gsl::narrow_cast or gsl::narow
-// - C26481: gsl::b.1 : don't use pointer arithmetic. Use span instead
-
-nssv_DISABLE_MSVC_WARNINGS(4455 26481 26472)
-    // nssv_DISABLE_CLANG_WARNINGS( "-Wuser-defined-literals" )
-    // nssv_DISABLE_GNUC_WARNINGS( -Wliteral-suffix )
-
-    namespace nonstd {
-  namespace sv_lite {
-
-#if nssv_CPP11_OR_GREATER
-
-  namespace detail {
-
-  // Expect tail call optimization to make length() non-recursive:
-
-  template <typename CharT> inline constexpr std::size_t length(CharT *s, std::size_t result = 0) {
-    return *s == '\0' ? result : length(s + 1, result + 1);
-  }
-
-  } // namespace detail
-
-#endif // nssv_CPP11_OR_GREATER
-
-  template <class CharT, class Traits = std::char_traits<CharT>> class basic_string_view;
-
-  //
-  // basic_string_view:
-  //
-
-  template <class CharT, class Traits /* = std::char_traits<CharT> */
-            >
-  class basic_string_view {
-  public:
-    // Member types:
-
-    typedef Traits traits_type;
-    typedef CharT value_type;
-
-    typedef CharT *pointer;
-    typedef CharT const *const_pointer;
-    typedef CharT &reference;
-    typedef CharT const &const_reference;
-
-    typedef const_pointer iterator;
-    typedef const_pointer const_iterator;
-    typedef std::reverse_iterator<const_iterator> reverse_iterator;
-    typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
-
-    typedef std::size_t size_type;
-    typedef std::ptrdiff_t difference_type;
-
-    // 24.4.2.1 Construction and assignment:
-
-    nssv_constexpr basic_string_view() nssv_noexcept : data_(nssv_nullptr), size_(0) {}
-
-#if nssv_CPP11_OR_GREATER
-    nssv_constexpr basic_string_view(basic_string_view const &other) nssv_noexcept = default;
-#else
-    nssv_constexpr basic_string_view(basic_string_view const &other) nssv_noexcept : data_(other.data_),
-                                                                                     size_(other.size_) {}
-#endif
-
-    nssv_constexpr basic_string_view(CharT const *s, size_type count) nssv_noexcept // non-standard noexcept
-        : data_(s),
-          size_(count) {}
-
-    nssv_constexpr basic_string_view(CharT const *s) nssv_noexcept // non-standard noexcept
-        : data_(s)
-#if nssv_CPP17_OR_GREATER
-        ,
-          size_(Traits::length(s))
-#elif nssv_CPP11_OR_GREATER
-        ,
-          size_(detail::length(s))
-#else
-        ,
-          size_(Traits::length(s))
-#endif
-    {
-    }
-
-    // Assignment:
-
-#if nssv_CPP11_OR_GREATER
-    nssv_constexpr14 basic_string_view &operator=(basic_string_view const &other) nssv_noexcept = default;
-#else
-    nssv_constexpr14 basic_string_view &operator=(basic_string_view const &other) nssv_noexcept {
-      data_ = other.data_;
-      size_ = other.size_;
-      return *this;
-    }
-#endif
-
-    // 24.4.2.2 Iterator support:
-
-    nssv_constexpr const_iterator begin() const nssv_noexcept { return data_; }
-    nssv_constexpr const_iterator end() const nssv_noexcept { return data_ + size_; }
-
-    nssv_constexpr const_iterator cbegin() const nssv_noexcept { return begin(); }
-    nssv_constexpr const_iterator cend() const nssv_noexcept { return end(); }
-
-    nssv_constexpr const_reverse_iterator rbegin() const nssv_noexcept { return const_reverse_iterator(end()); }
-    nssv_constexpr const_reverse_iterator rend() const nssv_noexcept { return const_reverse_iterator(begin()); }
-
-    nssv_constexpr const_reverse_iterator crbegin() const nssv_noexcept { return rbegin(); }
-    nssv_constexpr const_reverse_iterator crend() const nssv_noexcept { return rend(); }
-
-    // 24.4.2.3 Capacity:
-
-    nssv_constexpr size_type size() const nssv_noexcept { return size_; }
-    nssv_constexpr size_type length() const nssv_noexcept { return size_; }
-    nssv_constexpr size_type max_size() const nssv_noexcept { return (std::numeric_limits<size_type>::max)(); }
-
-    // since C++20
-    nssv_nodiscard nssv_constexpr bool empty() const nssv_noexcept { return 0 == size_; }
-
-    // 24.4.2.4 Element access:
-
-    nssv_constexpr const_reference operator[](size_type pos) const { return data_at(pos); }
-
-    nssv_constexpr14 const_reference at(size_type pos) const {
-#if nssv_CONFIG_NO_EXCEPTIONS
-      assert(pos < size());
-#else
-      if (pos >= size()) {
-        throw std::out_of_range("nonstd::string_view::at()");
-      }
-#endif
-      return data_at(pos);
-    }
-
-    nssv_constexpr const_reference front() const { return data_at(0); }
-    nssv_constexpr const_reference back() const { return data_at(size() - 1); }
-
-    nssv_constexpr const_pointer data() const nssv_noexcept { return data_; }
-
-    // 24.4.2.5 Modifiers:
-
-    nssv_constexpr14 void remove_prefix(size_type n) {
-      assert(n <= size());
-      data_ += n;
-      size_ -= n;
-    }
-
-    nssv_constexpr14 void remove_suffix(size_type n) {
-      assert(n <= size());
-      size_ -= n;
-    }
-
-    nssv_constexpr14 void swap(basic_string_view &other) nssv_noexcept {
-      using std::swap;
-      swap(data_, other.data_);
-      swap(size_, other.size_);
-    }
-
-    // 24.4.2.6 String operations:
-
-    size_type copy(CharT *dest, size_type n, size_type pos = 0) const {
-#if nssv_CONFIG_NO_EXCEPTIONS
-      assert(pos <= size());
-#else
-      if (pos > size()) {
-        throw std::out_of_range("nonstd::string_view::copy()");
-      }
-#endif
-      const size_type rlen = (std::min)(n, size() - pos);
-
-      (void)Traits::copy(dest, data() + pos, rlen);
-
-      return rlen;
-    }
-
-    nssv_constexpr14 basic_string_view substr(size_type pos = 0, size_type n = npos) const {
-#if nssv_CONFIG_NO_EXCEPTIONS
-      assert(pos <= size());
-#else
-      if (pos > size()) {
-        throw std::out_of_range("nonstd::string_view::substr()");
-      }
-#endif
-      return basic_string_view(data() + pos, (std::min)(n, size() - pos));
-    }
-
-    // compare(), 6x:
-
-    nssv_constexpr14 int compare(basic_string_view other) const nssv_noexcept // (1)
-    {
-      if (const int result = Traits::compare(data(), other.data(), (std::min)(size(), other.size()))) {
-        return result;
-      }
-
-      return size() == other.size() ? 0 : size() < other.size() ? -1 : 1;
-    }
-
-    nssv_constexpr int compare(size_type pos1, size_type n1, basic_string_view other) const // (2)
-    {
-      return substr(pos1, n1).compare(other);
-    }
-
-    nssv_constexpr int compare(size_type pos1, size_type n1, basic_string_view other, size_type pos2,
-                               size_type n2) const // (3)
-    {
-      return substr(pos1, n1).compare(other.substr(pos2, n2));
-    }
-
-    nssv_constexpr int compare(CharT const *s) const // (4)
-    {
-      return compare(basic_string_view(s));
-    }
-
-    nssv_constexpr int compare(size_type pos1, size_type n1, CharT const *s) const // (5)
-    {
-      return substr(pos1, n1).compare(basic_string_view(s));
-    }
-
-    nssv_constexpr int compare(size_type pos1, size_type n1, CharT const *s, size_type n2) const // (6)
-    {
-      return substr(pos1, n1).compare(basic_string_view(s, n2));
-    }
-
-    // 24.4.2.7 Searching:
-
-    // starts_with(), 3x, since C++20:
-
-    nssv_constexpr bool starts_with(basic_string_view v) const nssv_noexcept // (1)
-    {
-      return size() >= v.size() && compare(0, v.size(), v) == 0;
-    }
-
-    nssv_constexpr bool starts_with(CharT c) const nssv_noexcept // (2)
-    {
-      return starts_with(basic_string_view(&c, 1));
-    }
-
-    nssv_constexpr bool starts_with(CharT const *s) const // (3)
-    {
-      return starts_with(basic_string_view(s));
-    }
-
-    // ends_with(), 3x, since C++20:
-
-    nssv_constexpr bool ends_with(basic_string_view v) const nssv_noexcept // (1)
-    {
-      return size() >= v.size() && compare(size() - v.size(), npos, v) == 0;
-    }
-
-    nssv_constexpr bool ends_with(CharT c) const nssv_noexcept // (2)
-    {
-      return ends_with(basic_string_view(&c, 1));
-    }
-
-    nssv_constexpr bool ends_with(CharT const *s) const // (3)
-    {
-      return ends_with(basic_string_view(s));
-    }
-
-    // find(), 4x:
-
-    nssv_constexpr14 size_type find(basic_string_view v, size_type pos = 0) const nssv_noexcept // (1)
-    {
-      return assert(v.size() == 0 || v.data() != nssv_nullptr),
-             pos >= size() ? npos : to_pos(std::search(cbegin() + pos, cend(), v.cbegin(), v.cend(), Traits::eq));
-    }
-
-    nssv_constexpr14 size_type find(CharT c, size_type pos = 0) const nssv_noexcept // (2)
-    {
-      return find(basic_string_view(&c, 1), pos);
-    }
-
-    nssv_constexpr14 size_type find(CharT const *s, size_type pos, size_type n) const // (3)
-    {
-      return find(basic_string_view(s, n), pos);
-    }
-
-    nssv_constexpr14 size_type find(CharT const *s, size_type pos = 0) const // (4)
-    {
-      return find(basic_string_view(s), pos);
-    }
-
-    // rfind(), 4x:
-
-    nssv_constexpr14 size_type rfind(basic_string_view v, size_type pos = npos) const nssv_noexcept // (1)
-    {
-      if (size() < v.size()) {
-        return npos;
-      }
-
-      if (v.empty()) {
-        return (std::min)(size(), pos);
-      }
-
-      const_iterator last = cbegin() + (std::min)(size() - v.size(), pos) + v.size();
-      const_iterator result = std::find_end(cbegin(), last, v.cbegin(), v.cend(), Traits::eq);
-
-      return result != last ? size_type(result - cbegin()) : npos;
-    }
-
-    nssv_constexpr14 size_type rfind(CharT c, size_type pos = npos) const nssv_noexcept // (2)
-    {
-      return rfind(basic_string_view(&c, 1), pos);
-    }
-
-    nssv_constexpr14 size_type rfind(CharT const *s, size_type pos, size_type n) const // (3)
-    {
-      return rfind(basic_string_view(s, n), pos);
-    }
-
-    nssv_constexpr14 size_type rfind(CharT const *s, size_type pos = npos) const // (4)
-    {
-      return rfind(basic_string_view(s), pos);
-    }
-
-    // find_first_of(), 4x:
-
-    nssv_constexpr size_type find_first_of(basic_string_view v, size_type pos = 0) const nssv_noexcept // (1)
-    {
-      return pos >= size() ? npos
-                           : to_pos(std::find_first_of(cbegin() + pos, cend(), v.cbegin(), v.cend(), Traits::eq));
-    }
-
-    nssv_constexpr size_type find_first_of(CharT c, size_type pos = 0) const nssv_noexcept // (2)
-    {
-      return find_first_of(basic_string_view(&c, 1), pos);
-    }
-
-    nssv_constexpr size_type find_first_of(CharT const *s, size_type pos, size_type n) const // (3)
-    {
-      return find_first_of(basic_string_view(s, n), pos);
-    }
-
-    nssv_constexpr size_type find_first_of(CharT const *s, size_type pos = 0) const // (4)
-    {
-      return find_first_of(basic_string_view(s), pos);
-    }
-
-    // find_last_of(), 4x:
-
-    nssv_constexpr size_type find_last_of(basic_string_view v, size_type pos = npos) const nssv_noexcept // (1)
-    {
-      return empty() ? npos
-                     : pos >= size() ? find_last_of(v, size() - 1)
-                                     : to_pos(std::find_first_of(const_reverse_iterator(cbegin() + pos + 1), crend(),
-                                                                 v.cbegin(), v.cend(), Traits::eq));
-    }
-
-    nssv_constexpr size_type find_last_of(CharT c, size_type pos = npos) const nssv_noexcept // (2)
-    {
-      return find_last_of(basic_string_view(&c, 1), pos);
-    }
-
-    nssv_constexpr size_type find_last_of(CharT const *s, size_type pos, size_type count) const // (3)
-    {
-      return find_last_of(basic_string_view(s, count), pos);
-    }
-
-    nssv_constexpr size_type find_last_of(CharT const *s, size_type pos = npos) const // (4)
-    {
-      return find_last_of(basic_string_view(s), pos);
-    }
-
-    // find_first_not_of(), 4x:
-
-    nssv_constexpr size_type find_first_not_of(basic_string_view v, size_type pos = 0) const nssv_noexcept // (1)
-    {
-      return pos >= size() ? npos : to_pos(std::find_if(cbegin() + pos, cend(), not_in_view(v)));
-    }
-
-    nssv_constexpr size_type find_first_not_of(CharT c, size_type pos = 0) const nssv_noexcept // (2)
-    {
-      return find_first_not_of(basic_string_view(&c, 1), pos);
-    }
-
-    nssv_constexpr size_type find_first_not_of(CharT const *s, size_type pos, size_type count) const // (3)
-    {
-      return find_first_not_of(basic_string_view(s, count), pos);
-    }
-
-    nssv_constexpr size_type find_first_not_of(CharT const *s, size_type pos = 0) const // (4)
-    {
-      return find_first_not_of(basic_string_view(s), pos);
-    }
-
-    // find_last_not_of(), 4x:
-
-    nssv_constexpr size_type find_last_not_of(basic_string_view v, size_type pos = npos) const nssv_noexcept // (1)
-    {
-      return empty() ? npos
-                     : pos >= size()
-                           ? find_last_not_of(v, size() - 1)
-                           : to_pos(std::find_if(const_reverse_iterator(cbegin() + pos + 1), crend(), not_in_view(v)));
-    }
-
-    nssv_constexpr size_type find_last_not_of(CharT c, size_type pos = npos) const nssv_noexcept // (2)
-    {
-      return find_last_not_of(basic_string_view(&c, 1), pos);
-    }
-
-    nssv_constexpr size_type find_last_not_of(CharT const *s, size_type pos, size_type count) const // (3)
-    {
-      return find_last_not_of(basic_string_view(s, count), pos);
-    }
-
-    nssv_constexpr size_type find_last_not_of(CharT const *s, size_type pos = npos) const // (4)
-    {
-      return find_last_not_of(basic_string_view(s), pos);
-    }
-
-    // Constants:
-
-#if nssv_CPP17_OR_GREATER
-    static nssv_constexpr size_type npos = size_type(-1);
-#elif nssv_CPP11_OR_GREATER
-    enum : size_type { npos = size_type(-1) };
-#else
-    enum { npos = size_type(-1) };
-#endif
-
-  private:
-    struct not_in_view {
-      const basic_string_view v;
-
-      nssv_constexpr explicit not_in_view(basic_string_view v) : v(v) {}
-
-      nssv_constexpr bool operator()(CharT c) const { return npos == v.find_first_of(c); }
-    };
-
-    nssv_constexpr size_type to_pos(const_iterator it) const { return it == cend() ? npos : size_type(it - cbegin()); }
-
-    nssv_constexpr size_type to_pos(const_reverse_iterator it) const {
-      return it == crend() ? npos : size_type(crend() - it - 1);
-    }
-
-    nssv_constexpr const_reference data_at(size_type pos) const {
-#if nssv_BETWEEN(nssv_COMPILER_GNUC_VERSION, 1, 500)
-      return data_[pos];
-#else
-      return assert(pos < size()), data_[pos];
-#endif
-    }
-
-  private:
-    const_pointer data_;
-    size_type size_;
-
-  public:
-#if nssv_CONFIG_CONVERSION_STD_STRING_CLASS_METHODS
-
-    template <class Allocator>
-    basic_string_view(std::basic_string<CharT, Traits, Allocator> const &s) nssv_noexcept : data_(s.data()),
-                                                                                            size_(s.size()) {}
-
-#if nssv_HAVE_EXPLICIT_CONVERSION
-
-    template <class Allocator> explicit operator std::basic_string<CharT, Traits, Allocator>() const {
-      return to_string(Allocator());
-    }
-
-#endif // nssv_HAVE_EXPLICIT_CONVERSION
-
-#if nssv_CPP11_OR_GREATER
-
-    template <class Allocator = std::allocator<CharT>>
-    std::basic_string<CharT, Traits, Allocator> to_string(Allocator const &a = Allocator()) const {
-      return std::basic_string<CharT, Traits, Allocator>(begin(), end(), a);
-    }
-
-#else
-
-    std::basic_string<CharT, Traits> to_string() const { return std::basic_string<CharT, Traits>(begin(), end()); }
-
-    template <class Allocator> std::basic_string<CharT, Traits, Allocator> to_string(Allocator const &a) const {
-      return std::basic_string<CharT, Traits, Allocator>(begin(), end(), a);
-    }
-
-#endif // nssv_CPP11_OR_GREATER
-
-#endif // nssv_CONFIG_CONVERSION_STD_STRING_CLASS_METHODS
-  };
-
-  //
-  // Non-member functions:
-  //
-
-  // 24.4.3 Non-member comparison functions:
-  // lexicographically compare two string views (function template):
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator==(basic_string_view<CharT, Traits> lhs,
-                                 basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) == 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator!=(basic_string_view<CharT, Traits> lhs,
-                                 basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) != 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<(basic_string_view<CharT, Traits> lhs,
-                                basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) < 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<=(basic_string_view<CharT, Traits> lhs,
-                                 basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) <= 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>(basic_string_view<CharT, Traits> lhs,
-                                basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) > 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>=(basic_string_view<CharT, Traits> lhs,
-                                 basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) >= 0;
-  }
-
-  // Let S be basic_string_view<CharT, Traits>, and sv be an instance of S.
-  // Implementations shall provide sufficient additional overloads marked
-  // constexpr and noexcept so that an object t with an implicit conversion
-  // to S can be compared according to Table 67.
-
-#if !nssv_CPP11_OR_GREATER || nssv_BETWEEN(nssv_COMPILER_MSVC_VERSION, 100, 141)
-
-  // accomodate for older compilers:
-
-  // ==
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator==(basic_string_view<CharT, Traits> lhs, char const *rhs) nssv_noexcept {
-    return lhs.compare(rhs) == 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator==(char const *lhs, basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return rhs.compare(lhs) == 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator==(basic_string_view<CharT, Traits> lhs,
-                                 std::basic_string<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.size() == rhs.size() && lhs.compare(rhs) == 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator==(std::basic_string<CharT, Traits> rhs,
-                                 basic_string_view<CharT, Traits> lhs) nssv_noexcept {
-    return lhs.size() == rhs.size() && lhs.compare(rhs) == 0;
-  }
-
-  // !=
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator!=(basic_string_view<CharT, Traits> lhs, char const *rhs) nssv_noexcept {
-    return lhs.compare(rhs) != 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator!=(char const *lhs, basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return rhs.compare(lhs) != 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator!=(basic_string_view<CharT, Traits> lhs,
-                                 std::basic_string<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.size() != rhs.size() && lhs.compare(rhs) != 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator!=(std::basic_string<CharT, Traits> rhs,
-                                 basic_string_view<CharT, Traits> lhs) nssv_noexcept {
-    return lhs.size() != rhs.size() || rhs.compare(lhs) != 0;
-  }
-
-  // <
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<(basic_string_view<CharT, Traits> lhs, char const *rhs) nssv_noexcept {
-    return lhs.compare(rhs) < 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<(char const *lhs, basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return rhs.compare(lhs) > 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<(basic_string_view<CharT, Traits> lhs,
-                                std::basic_string<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) < 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<(std::basic_string<CharT, Traits> rhs,
-                                basic_string_view<CharT, Traits> lhs) nssv_noexcept {
-    return rhs.compare(lhs) > 0;
-  }
-
-  // <=
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<=(basic_string_view<CharT, Traits> lhs, char const *rhs) nssv_noexcept {
-    return lhs.compare(rhs) <= 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<=(char const *lhs, basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return rhs.compare(lhs) >= 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<=(basic_string_view<CharT, Traits> lhs,
-                                 std::basic_string<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) <= 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<=(std::basic_string<CharT, Traits> rhs,
-                                 basic_string_view<CharT, Traits> lhs) nssv_noexcept {
-    return rhs.compare(lhs) >= 0;
-  }
-
-  // >
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>(basic_string_view<CharT, Traits> lhs, char const *rhs) nssv_noexcept {
-    return lhs.compare(rhs) > 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>(char const *lhs, basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return rhs.compare(lhs) < 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>(basic_string_view<CharT, Traits> lhs,
-                                std::basic_string<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) > 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>(std::basic_string<CharT, Traits> rhs,
-                                basic_string_view<CharT, Traits> lhs) nssv_noexcept {
-    return rhs.compare(lhs) < 0;
-  }
-
-  // >=
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>=(basic_string_view<CharT, Traits> lhs, char const *rhs) nssv_noexcept {
-    return lhs.compare(rhs) >= 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>=(char const *lhs, basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return rhs.compare(lhs) <= 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>=(basic_string_view<CharT, Traits> lhs,
-                                 std::basic_string<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) >= 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>=(std::basic_string<CharT, Traits> rhs,
-                                 basic_string_view<CharT, Traits> lhs) nssv_noexcept {
-    return rhs.compare(lhs) <= 0;
-  }
-
-#else // newer compilers:
-
-#define nssv_BASIC_STRING_VIEW_I(T, U) typename std::decay<basic_string_view<T, U>>::type
-
-#if nssv_BETWEEN(nssv_COMPILER_MSVC_VERSION, 140, 150)
-#define nssv_MSVC_ORDER(x) , int = x
-#else
-#define nssv_MSVC_ORDER(x) /*, int=x*/
-#endif
-
-  // ==
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(1)>
-  nssv_constexpr bool operator==(basic_string_view<CharT, Traits> lhs,
-                                 nssv_BASIC_STRING_VIEW_I(CharT, Traits) rhs) nssv_noexcept {
-    return lhs.compare(rhs) == 0;
-  }
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(2)>
-  nssv_constexpr bool operator==(nssv_BASIC_STRING_VIEW_I(CharT, Traits) lhs,
-                                 basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.size() == rhs.size() && lhs.compare(rhs) == 0;
-  }
-
-  // !=
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(1)>
-  nssv_constexpr bool operator!=(basic_string_view<CharT, Traits> lhs,
-                                 nssv_BASIC_STRING_VIEW_I(CharT, Traits) rhs) nssv_noexcept {
-    return lhs.size() != rhs.size() || lhs.compare(rhs) != 0;
-  }
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(2)>
-  nssv_constexpr bool operator!=(nssv_BASIC_STRING_VIEW_I(CharT, Traits) lhs,
-                                 basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) != 0;
-  }
-
-  // <
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(1)>
-  nssv_constexpr bool operator<(basic_string_view<CharT, Traits> lhs,
-                                nssv_BASIC_STRING_VIEW_I(CharT, Traits) rhs) nssv_noexcept {
-    return lhs.compare(rhs) < 0;
-  }
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(2)>
-  nssv_constexpr bool operator<(nssv_BASIC_STRING_VIEW_I(CharT, Traits) lhs,
-                                basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) < 0;
-  }
-
-  // <=
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(1)>
-  nssv_constexpr bool operator<=(basic_string_view<CharT, Traits> lhs,
-                                 nssv_BASIC_STRING_VIEW_I(CharT, Traits) rhs) nssv_noexcept {
-    return lhs.compare(rhs) <= 0;
-  }
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(2)>
-  nssv_constexpr bool operator<=(nssv_BASIC_STRING_VIEW_I(CharT, Traits) lhs,
-                                 basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) <= 0;
-  }
-
-  // >
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(1)>
-  nssv_constexpr bool operator>(basic_string_view<CharT, Traits> lhs,
-                                nssv_BASIC_STRING_VIEW_I(CharT, Traits) rhs) nssv_noexcept {
-    return lhs.compare(rhs) > 0;
-  }
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(2)>
-  nssv_constexpr bool operator>(nssv_BASIC_STRING_VIEW_I(CharT, Traits) lhs,
-                                basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) > 0;
-  }
-
-  // >=
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(1)>
-  nssv_constexpr bool operator>=(basic_string_view<CharT, Traits> lhs,
-                                 nssv_BASIC_STRING_VIEW_I(CharT, Traits) rhs) nssv_noexcept {
-    return lhs.compare(rhs) >= 0;
-  }
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(2)>
-  nssv_constexpr bool operator>=(nssv_BASIC_STRING_VIEW_I(CharT, Traits) lhs,
-                                 basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) >= 0;
-  }
-
-#undef nssv_MSVC_ORDER
-#undef nssv_BASIC_STRING_VIEW_I
-
-#endif // compiler-dependent approach to comparisons
-
-  // 24.4.4 Inserters and extractors:
-
-  namespace detail {
-
-  template <class Stream> void write_padding(Stream &os, std::streamsize n) {
-    for (std::streamsize i = 0; i < n; ++i)
-      os.rdbuf()->sputc(os.fill());
-  }
-
-  template <class Stream, class View> Stream &write_to_stream(Stream &os, View const &sv) {
-    typename Stream::sentry sentry(os);
-
-    if (!os)
-      return os;
-
-    const std::streamsize length = static_cast<std::streamsize>(sv.length());
-
-    // Whether, and how, to pad:
-    const bool pad = (length < os.width());
-    const bool left_pad = pad && (os.flags() & std::ios_base::adjustfield) == std::ios_base::right;
-
-    if (left_pad)
-      write_padding(os, os.width() - length);
-
-    // Write span characters:
-    os.rdbuf()->sputn(sv.begin(), length);
-
-    if (pad && !left_pad)
-      write_padding(os, os.width() - length);
-
-    // Reset output stream width:
-    os.width(0);
-
-    return os;
-  }
-
-  } // namespace detail
-
-  template <class CharT, class Traits>
-  std::basic_ostream<CharT, Traits> &operator<<(std::basic_ostream<CharT, Traits> &os,
-                                                basic_string_view<CharT, Traits> sv) {
-    return detail::write_to_stream(os, sv);
-  }
-
-  // Several typedefs for common character types are provided:
-
-  typedef basic_string_view<char> string_view;
-  typedef basic_string_view<wchar_t> wstring_view;
-#if nssv_HAVE_WCHAR16_T
-  typedef basic_string_view<char16_t> u16string_view;
-  typedef basic_string_view<char32_t> u32string_view;
-#endif
-
-  } // namespace sv_lite
-} // namespace nonstd::sv_lite
-
-//
-// 24.4.6 Suffix for basic_string_view literals:
-//
-
-#if nssv_HAVE_USER_DEFINED_LITERALS
-
-namespace nonstd {
-nssv_inline_ns namespace literals {
-  nssv_inline_ns namespace string_view_literals {
-
-#if nssv_CONFIG_STD_SV_OPERATOR && nssv_HAVE_STD_DEFINED_LITERALS
-
-    nssv_constexpr nonstd::sv_lite::string_view operator"" sv(const char *str, size_t len) nssv_noexcept // (1)
-    {
-      return nonstd::sv_lite::string_view {str, len};
-    }
-
-    nssv_constexpr nonstd::sv_lite::u16string_view operator"" sv(const char16_t *str, size_t len) nssv_noexcept // (2)
-    {
-      return nonstd::sv_lite::u16string_view {str, len};
-    }
-
-    nssv_constexpr nonstd::sv_lite::u32string_view operator"" sv(const char32_t *str, size_t len) nssv_noexcept // (3)
-    {
-      return nonstd::sv_lite::u32string_view {str, len};
-    }
-
-    nssv_constexpr nonstd::sv_lite::wstring_view operator"" sv(const wchar_t *str, size_t len) nssv_noexcept // (4)
-    {
-      return nonstd::sv_lite::wstring_view {str, len};
-    }
-
-#endif // nssv_CONFIG_STD_SV_OPERATOR && nssv_HAVE_STD_DEFINED_LITERALS
-
-#if nssv_CONFIG_USR_SV_OPERATOR
-
-    nssv_constexpr nonstd::sv_lite::string_view operator"" _sv(const char *str, size_t len) nssv_noexcept // (1)
-    {
-      return nonstd::sv_lite::string_view {str, len};
-    }
-
-    nssv_constexpr nonstd::sv_lite::u16string_view operator"" _sv(const char16_t *str, size_t len) nssv_noexcept // (2)
-    {
-      return nonstd::sv_lite::u16string_view {str, len};
-    }
-
-    nssv_constexpr nonstd::sv_lite::u32string_view operator"" _sv(const char32_t *str, size_t len) nssv_noexcept // (3)
-    {
-      return nonstd::sv_lite::u32string_view {str, len};
-    }
-
-    nssv_constexpr nonstd::sv_lite::wstring_view operator"" _sv(const wchar_t *str, size_t len) nssv_noexcept // (4)
-    {
-      return nonstd::sv_lite::wstring_view {str, len};
-    }
-
-#endif // nssv_CONFIG_USR_SV_OPERATOR
-  }
-}
-} // namespace nonstd
-
-#endif
-
-//
-// Extensions for std::string:
-//
-
-#if nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS
-
-namespace nonstd {
-namespace sv_lite {
-
-// Exclude MSVC 14 (19.00): it yields ambiguous to_string():
-
-#if nssv_CPP11_OR_GREATER && nssv_COMPILER_MSVC_VERSION != 140
-
-template <class CharT, class Traits, class Allocator = std::allocator<CharT>>
-std::basic_string<CharT, Traits, Allocator> to_string(basic_string_view<CharT, Traits> v,
-                                                      Allocator const &a = Allocator()) {
-  return std::basic_string<CharT, Traits, Allocator>(v.begin(), v.end(), a);
-}
-
-#else
-
-template <class CharT, class Traits> std::basic_string<CharT, Traits> to_string(basic_string_view<CharT, Traits> v) {
-  return std::basic_string<CharT, Traits>(v.begin(), v.end());
-}
-
-template <class CharT, class Traits, class Allocator>
-std::basic_string<CharT, Traits, Allocator> to_string(basic_string_view<CharT, Traits> v, Allocator const &a) {
-  return std::basic_string<CharT, Traits, Allocator>(v.begin(), v.end(), a);
-}
-
-#endif // nssv_CPP11_OR_GREATER
-
-template <class CharT, class Traits, class Allocator>
-basic_string_view<CharT, Traits> to_string_view(std::basic_string<CharT, Traits, Allocator> const &s) {
-  return basic_string_view<CharT, Traits>(s.data(), s.size());
-}
-
-} // namespace sv_lite
-} // namespace nonstd
-
-#endif // nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS
-
-//
-// make types and algorithms available in namespace nonstd:
-//
-
-namespace nonstd {
-
-using sv_lite::basic_string_view;
-using sv_lite::string_view;
-using sv_lite::wstring_view;
-
-#if nssv_HAVE_WCHAR16_T
-using sv_lite::u16string_view;
-#endif
-#if nssv_HAVE_WCHAR32_T
-using sv_lite::u32string_view;
-#endif
-
-// literal "sv"
-
-using sv_lite::operator==;
-using sv_lite::operator!=;
-using sv_lite::operator<;
-using sv_lite::operator<=;
-using sv_lite::operator>;
-using sv_lite::operator>=;
-
-using sv_lite::operator<<;
-
-#if nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS
-using sv_lite::to_string;
-using sv_lite::to_string_view;
-#endif
-
-} // namespace nonstd
-
-// 24.4.5 Hash support (C++11):
-
-// Note: The hash value of a string view object is equal to the hash value of
-// the corresponding string object.
-
-#if nssv_HAVE_STD_HASH
-
-#include <functional>
-
-namespace std {
-
-template <> struct hash<nonstd::string_view> {
-public:
-  std::size_t operator()(nonstd::string_view v) const nssv_noexcept {
-    return std::hash<std::string>()(std::string(v.data(), v.size()));
-  }
-};
-
-template <> struct hash<nonstd::wstring_view> {
-public:
-  std::size_t operator()(nonstd::wstring_view v) const nssv_noexcept {
-    return std::hash<std::wstring>()(std::wstring(v.data(), v.size()));
-  }
-};
-
-template <> struct hash<nonstd::u16string_view> {
-public:
-  std::size_t operator()(nonstd::u16string_view v) const nssv_noexcept {
-    return std::hash<std::u16string>()(std::u16string(v.data(), v.size()));
-  }
-};
-
-template <> struct hash<nonstd::u32string_view> {
-public:
-  std::size_t operator()(nonstd::u32string_view v) const nssv_noexcept {
-    return std::hash<std::u32string>()(std::u32string(v.data(), v.size()));
-  }
-};
-
-} // namespace std
-
-#endif // nssv_HAVE_STD_HASH
-
-nssv_RESTORE_WARNINGS()
-
-#endif // nssv_HAVE_STD_STRING_VIEW
-#endif // NONSTD_SV_LITE_H_INCLUDED
diff --git a/include/inja/token.hpp b/include/inja/token.hpp
index 1904c4d..5391342 100644
--- a/include/inja/token.hpp
+++ b/include/inja/token.hpp
@@ -2,8 +2,8 @@
 #define INCLUDE_INJA_TOKEN_HPP_
 
 #include <string>
+#include <string_view>
 
-#include "string_view.hpp"
 
 namespace inja {
 
@@ -50,10 +50,10 @@
   };
   
   Kind kind {Kind::Unknown};
-  nonstd::string_view text;
+  std::string_view text;
 
   explicit constexpr Token() = default;
-  explicit constexpr Token(Kind kind, nonstd::string_view text) : kind(kind), text(text) {}
+  explicit constexpr Token(Kind kind, std::string_view text) : kind(kind), text(text) {}
 
   std::string describe() const {
     switch (kind) {
diff --git a/include/inja/utils.hpp b/include/inja/utils.hpp
index d90137a..c1d13d5 100644
--- a/include/inja/utils.hpp
+++ b/include/inja/utils.hpp
@@ -4,39 +4,40 @@
 #include <algorithm>
 #include <fstream>
 #include <string>
+#include <string_view>
 #include <utility>
 
 #include "exceptions.hpp"
-#include "string_view.hpp"
+
 
 namespace inja {
 
 namespace string_view {
-inline nonstd::string_view slice(nonstd::string_view view, size_t start, size_t end) {
+inline std::string_view slice(std::string_view view, size_t start, size_t end) {
   start = std::min(start, view.size());
   end = std::min(std::max(start, end), view.size());
   return view.substr(start, end - start);
 }
 
-inline std::pair<nonstd::string_view, nonstd::string_view> split(nonstd::string_view view, char Separator) {
+inline std::pair<std::string_view, std::string_view> split(std::string_view view, char Separator) {
   size_t idx = view.find(Separator);
-  if (idx == nonstd::string_view::npos) {
-    return std::make_pair(view, nonstd::string_view());
+  if (idx == std::string_view::npos) {
+    return std::make_pair(view, std::string_view());
   }
-  return std::make_pair(slice(view, 0, idx), slice(view, idx + 1, nonstd::string_view::npos));
+  return std::make_pair(slice(view, 0, idx), slice(view, idx + 1, std::string_view::npos));
 }
 
-inline bool starts_with(nonstd::string_view view, nonstd::string_view prefix) {
+inline bool starts_with(std::string_view view, std::string_view prefix) {
   return (view.size() >= prefix.size() && view.compare(0, prefix.size(), prefix) == 0);
 }
 } // namespace string_view
 
-inline SourceLocation get_source_location(nonstd::string_view content, size_t pos) {
+inline SourceLocation get_source_location(std::string_view content, size_t pos) {
   // Get line and offset position (starts at 1:1)
   auto sliced = string_view::slice(content, 0, pos);
   std::size_t last_newline = sliced.rfind("\n");
 
-  if (last_newline == nonstd::string_view::npos) {
+  if (last_newline == std::string_view::npos) {
     return {1, sliced.length() + 1};
   }
 
diff --git a/single_include/inja/inja.hpp b/single_include/inja/inja.hpp
index 1bd8644..e1e203e 100644
--- a/single_include/inja/inja.hpp
+++ b/single_include/inja/inja.hpp
@@ -58,6 +58,7 @@
 #include <memory>
 #include <sstream>
 #include <string>
+#include <string_view>
 
 // #include "config.hpp"
 #ifndef INCLUDE_INJA_CONFIG_HPP_
@@ -66,1424 +67,6 @@
 #include <functional>
 #include <string>
 
-// #include "string_view.hpp"
-// Copyright 2017-2019 by Martin Moene
-//
-// string-view lite, a C++17-like string_view for C++98 and later.
-// For more information see https://github.com/martinmoene/string-view-lite
-//
-// Distributed under the Boost Software License, Version 1.0.
-// (See accompanying file LICENSE.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-
-
-
-#ifndef NONSTD_SV_LITE_H_INCLUDED
-#define NONSTD_SV_LITE_H_INCLUDED
-
-#define string_view_lite_MAJOR 1
-#define string_view_lite_MINOR 4
-#define string_view_lite_PATCH 0
-
-#define string_view_lite_VERSION                                                                                       \
-  nssv_STRINGIFY(string_view_lite_MAJOR) "." nssv_STRINGIFY(string_view_lite_MINOR) "." nssv_STRINGIFY(                \
-      string_view_lite_PATCH)
-
-#define nssv_STRINGIFY(x) nssv_STRINGIFY_(x)
-#define nssv_STRINGIFY_(x) #x
-
-// string-view lite configuration:
-
-#define nssv_STRING_VIEW_DEFAULT 0
-#define nssv_STRING_VIEW_NONSTD 1
-#define nssv_STRING_VIEW_STD 2
-
-#if !defined(nssv_CONFIG_SELECT_STRING_VIEW)
-#define nssv_CONFIG_SELECT_STRING_VIEW (nssv_HAVE_STD_STRING_VIEW ? nssv_STRING_VIEW_STD : nssv_STRING_VIEW_NONSTD)
-#endif
-
-#if defined(nssv_CONFIG_SELECT_STD_STRING_VIEW) || defined(nssv_CONFIG_SELECT_NONSTD_STRING_VIEW)
-#error nssv_CONFIG_SELECT_STD_STRING_VIEW and nssv_CONFIG_SELECT_NONSTD_STRING_VIEW are deprecated and removed, please use nssv_CONFIG_SELECT_STRING_VIEW=nssv_STRING_VIEW_...
-#endif
-
-#ifndef nssv_CONFIG_STD_SV_OPERATOR
-#define nssv_CONFIG_STD_SV_OPERATOR 0
-#endif
-
-#ifndef nssv_CONFIG_USR_SV_OPERATOR
-#define nssv_CONFIG_USR_SV_OPERATOR 1
-#endif
-
-#ifdef nssv_CONFIG_CONVERSION_STD_STRING
-#define nssv_CONFIG_CONVERSION_STD_STRING_CLASS_METHODS nssv_CONFIG_CONVERSION_STD_STRING
-#define nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS nssv_CONFIG_CONVERSION_STD_STRING
-#endif
-
-#ifndef nssv_CONFIG_CONVERSION_STD_STRING_CLASS_METHODS
-#define nssv_CONFIG_CONVERSION_STD_STRING_CLASS_METHODS 1
-#endif
-
-#ifndef nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS
-#define nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS 1
-#endif
-
-// Control presence of exception handling (try and auto discover):
-
-#ifndef nssv_CONFIG_NO_EXCEPTIONS
-#if defined(__cpp_exceptions) || defined(__EXCEPTIONS) || defined(_CPPUNWIND)
-#define nssv_CONFIG_NO_EXCEPTIONS 0
-#else
-#define nssv_CONFIG_NO_EXCEPTIONS 1
-#endif
-#endif
-
-// C++ language version detection (C++20 is speculative):
-// Note: VC14.0/1900 (VS2015) lacks too much from C++14.
-
-#ifndef nssv_CPLUSPLUS
-#if defined(_MSVC_LANG) && !defined(__clang__)
-#define nssv_CPLUSPLUS (_MSC_VER == 1900 ? 201103L : _MSVC_LANG)
-#else
-#define nssv_CPLUSPLUS __cplusplus
-#endif
-#endif
-
-#define nssv_CPP98_OR_GREATER (nssv_CPLUSPLUS >= 199711L)
-#define nssv_CPP11_OR_GREATER (nssv_CPLUSPLUS >= 201103L)
-#define nssv_CPP11_OR_GREATER_ (nssv_CPLUSPLUS >= 201103L)
-#define nssv_CPP14_OR_GREATER (nssv_CPLUSPLUS >= 201402L)
-#define nssv_CPP17_OR_GREATER (nssv_CPLUSPLUS >= 201703L)
-#define nssv_CPP20_OR_GREATER (nssv_CPLUSPLUS >= 202000L)
-
-// use C++17 std::string_view if available and requested:
-
-#if nssv_CPP17_OR_GREATER && defined(__has_include)
-#if __has_include(<string_view> )
-#define nssv_HAVE_STD_STRING_VIEW 1
-#else
-#define nssv_HAVE_STD_STRING_VIEW 0
-#endif
-#else
-#define nssv_HAVE_STD_STRING_VIEW 0
-#endif
-
-#define nssv_USES_STD_STRING_VIEW                                                                                      \
-  ((nssv_CONFIG_SELECT_STRING_VIEW == nssv_STRING_VIEW_STD) ||                                                         \
-   ((nssv_CONFIG_SELECT_STRING_VIEW == nssv_STRING_VIEW_DEFAULT) && nssv_HAVE_STD_STRING_VIEW))
-
-#define nssv_HAVE_STARTS_WITH (nssv_CPP20_OR_GREATER || !nssv_USES_STD_STRING_VIEW)
-#define nssv_HAVE_ENDS_WITH nssv_HAVE_STARTS_WITH
-
-//
-// Use C++17 std::string_view:
-//
-
-#if nssv_USES_STD_STRING_VIEW
-
-#include <string_view>
-
-// Extensions for std::string:
-
-#if nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS
-
-namespace nonstd {
-
-template <class CharT, class Traits, class Allocator = std::allocator<CharT>>
-std::basic_string<CharT, Traits, Allocator> to_string(std::basic_string_view<CharT, Traits> v,
-                                                      Allocator const &a = Allocator()) {
-  return std::basic_string<CharT, Traits, Allocator>(v.begin(), v.end(), a);
-}
-
-template <class CharT, class Traits, class Allocator>
-std::basic_string_view<CharT, Traits> to_string_view(std::basic_string<CharT, Traits, Allocator> const &s) {
-  return std::basic_string_view<CharT, Traits>(s.data(), s.size());
-}
-
-// Literal operators sv and _sv:
-
-#if nssv_CONFIG_STD_SV_OPERATOR
-
-using namespace std::literals::string_view_literals;
-
-#endif
-
-#if nssv_CONFIG_USR_SV_OPERATOR
-
-inline namespace literals {
-inline namespace string_view_literals {
-
-constexpr std::string_view operator"" _sv(const char *str, size_t len) noexcept // (1)
-{
-  return std::string_view {str, len};
-}
-
-constexpr std::u16string_view operator"" _sv(const char16_t *str, size_t len) noexcept // (2)
-{
-  return std::u16string_view {str, len};
-}
-
-constexpr std::u32string_view operator"" _sv(const char32_t *str, size_t len) noexcept // (3)
-{
-  return std::u32string_view {str, len};
-}
-
-constexpr std::wstring_view operator"" _sv(const wchar_t *str, size_t len) noexcept // (4)
-{
-  return std::wstring_view {str, len};
-}
-
-} // namespace string_view_literals
-} // namespace literals
-
-#endif // nssv_CONFIG_USR_SV_OPERATOR
-
-} // namespace nonstd
-
-#endif // nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS
-
-namespace nonstd {
-
-using std::basic_string_view;
-using std::string_view;
-using std::u16string_view;
-using std::u32string_view;
-using std::wstring_view;
-
-// literal "sv" and "_sv", see above
-
-using std::operator==;
-using std::operator!=;
-using std::operator<;
-using std::operator<=;
-using std::operator>;
-using std::operator>=;
-
-using std::operator<<;
-
-} // namespace nonstd
-
-#else // nssv_HAVE_STD_STRING_VIEW
-
-//
-// Before C++17: use string_view lite:
-//
-
-// Compiler versions:
-//
-// MSVC++ 6.0  _MSC_VER == 1200 (Visual Studio 6.0)
-// MSVC++ 7.0  _MSC_VER == 1300 (Visual Studio .NET 2002)
-// MSVC++ 7.1  _MSC_VER == 1310 (Visual Studio .NET 2003)
-// MSVC++ 8.0  _MSC_VER == 1400 (Visual Studio 2005)
-// MSVC++ 9.0  _MSC_VER == 1500 (Visual Studio 2008)
-// MSVC++ 10.0 _MSC_VER == 1600 (Visual Studio 2010)
-// MSVC++ 11.0 _MSC_VER == 1700 (Visual Studio 2012)
-// MSVC++ 12.0 _MSC_VER == 1800 (Visual Studio 2013)
-// MSVC++ 14.0 _MSC_VER == 1900 (Visual Studio 2015)
-// MSVC++ 14.1 _MSC_VER >= 1910 (Visual Studio 2017)
-
-#if defined(_MSC_VER) && !defined(__clang__)
-#define nssv_COMPILER_MSVC_VER (_MSC_VER)
-#define nssv_COMPILER_MSVC_VERSION (_MSC_VER / 10 - 10 * (5 + (_MSC_VER < 1900)))
-#else
-#define nssv_COMPILER_MSVC_VER 0
-#define nssv_COMPILER_MSVC_VERSION 0
-#endif
-
-#define nssv_COMPILER_VERSION(major, minor, patch) (10 * (10 * (major) + (minor)) + (patch))
-
-#if defined(__clang__)
-#define nssv_COMPILER_CLANG_VERSION nssv_COMPILER_VERSION(__clang_major__, __clang_minor__, __clang_patchlevel__)
-#else
-#define nssv_COMPILER_CLANG_VERSION 0
-#endif
-
-#if defined(__GNUC__) && !defined(__clang__)
-#define nssv_COMPILER_GNUC_VERSION nssv_COMPILER_VERSION(__GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__)
-#else
-#define nssv_COMPILER_GNUC_VERSION 0
-#endif
-
-// half-open range [lo..hi):
-#define nssv_BETWEEN(v, lo, hi) ((lo) <= (v) && (v) < (hi))
-
-// Presence of language and library features:
-
-#ifdef _HAS_CPP0X
-#define nssv_HAS_CPP0X _HAS_CPP0X
-#else
-#define nssv_HAS_CPP0X 0
-#endif
-
-// Unless defined otherwise below, consider VC14 as C++11 for variant-lite:
-
-#if nssv_COMPILER_MSVC_VER >= 1900
-#undef nssv_CPP11_OR_GREATER
-#define nssv_CPP11_OR_GREATER 1
-#endif
-
-#define nssv_CPP11_90 (nssv_CPP11_OR_GREATER_ || nssv_COMPILER_MSVC_VER >= 1500)
-#define nssv_CPP11_100 (nssv_CPP11_OR_GREATER_ || nssv_COMPILER_MSVC_VER >= 1600)
-#define nssv_CPP11_110 (nssv_CPP11_OR_GREATER_ || nssv_COMPILER_MSVC_VER >= 1700)
-#define nssv_CPP11_120 (nssv_CPP11_OR_GREATER_ || nssv_COMPILER_MSVC_VER >= 1800)
-#define nssv_CPP11_140 (nssv_CPP11_OR_GREATER_ || nssv_COMPILER_MSVC_VER >= 1900)
-#define nssv_CPP11_141 (nssv_CPP11_OR_GREATER_ || nssv_COMPILER_MSVC_VER >= 1910)
-
-#define nssv_CPP14_000 (nssv_CPP14_OR_GREATER)
-#define nssv_CPP17_000 (nssv_CPP17_OR_GREATER)
-
-// Presence of C++11 language features:
-
-#define nssv_HAVE_CONSTEXPR_11 nssv_CPP11_140
-#define nssv_HAVE_EXPLICIT_CONVERSION nssv_CPP11_140
-#define nssv_HAVE_INLINE_NAMESPACE nssv_CPP11_140
-#define nssv_HAVE_NOEXCEPT nssv_CPP11_140
-#define nssv_HAVE_NULLPTR nssv_CPP11_100
-#define nssv_HAVE_REF_QUALIFIER nssv_CPP11_140
-#define nssv_HAVE_UNICODE_LITERALS nssv_CPP11_140
-#define nssv_HAVE_USER_DEFINED_LITERALS nssv_CPP11_140
-#define nssv_HAVE_WCHAR16_T nssv_CPP11_100
-#define nssv_HAVE_WCHAR32_T nssv_CPP11_100
-
-#if !((nssv_CPP11_OR_GREATER && nssv_COMPILER_CLANG_VERSION) || nssv_BETWEEN(nssv_COMPILER_CLANG_VERSION, 300, 400))
-#define nssv_HAVE_STD_DEFINED_LITERALS nssv_CPP11_140
-#else
-#define nssv_HAVE_STD_DEFINED_LITERALS 0
-#endif
-
-// Presence of C++14 language features:
-
-#define nssv_HAVE_CONSTEXPR_14 nssv_CPP14_000
-
-// Presence of C++17 language features:
-
-#define nssv_HAVE_NODISCARD nssv_CPP17_000
-
-// Presence of C++ library features:
-
-#define nssv_HAVE_STD_HASH nssv_CPP11_120
-
-// C++ feature usage:
-
-#if nssv_HAVE_CONSTEXPR_11
-#define nssv_constexpr constexpr
-#else
-#define nssv_constexpr /*constexpr*/
-#endif
-
-#if nssv_HAVE_CONSTEXPR_14
-#define nssv_constexpr14 constexpr
-#else
-#define nssv_constexpr14 /*constexpr*/
-#endif
-
-#if nssv_HAVE_EXPLICIT_CONVERSION
-#define nssv_explicit explicit
-#else
-#define nssv_explicit /*explicit*/
-#endif
-
-#if nssv_HAVE_INLINE_NAMESPACE
-#define nssv_inline_ns inline
-#else
-#define nssv_inline_ns /*inline*/
-#endif
-
-#if nssv_HAVE_NOEXCEPT
-#define nssv_noexcept noexcept
-#else
-#define nssv_noexcept /*noexcept*/
-#endif
-
-//#if nssv_HAVE_REF_QUALIFIER
-//# define nssv_ref_qual  &
-//# define nssv_refref_qual  &&
-//#else
-//# define nssv_ref_qual  /*&*/
-//# define nssv_refref_qual  /*&&*/
-//#endif
-
-#if nssv_HAVE_NULLPTR
-#define nssv_nullptr nullptr
-#else
-#define nssv_nullptr NULL
-#endif
-
-#if nssv_HAVE_NODISCARD
-#define nssv_nodiscard [[nodiscard]]
-#else
-#define nssv_nodiscard /*[[nodiscard]]*/
-#endif
-
-// Additional includes:
-
-#include <algorithm>
-#include <cassert>
-#include <iterator>
-#include <limits>
-#include <ostream>
-#include <string> // std::char_traits<>
-
-#if !nssv_CONFIG_NO_EXCEPTIONS
-#include <stdexcept>
-#endif
-
-#if nssv_CPP11_OR_GREATER
-#include <type_traits>
-#endif
-
-// Clang, GNUC, MSVC warning suppression macros:
-
-#if defined(__clang__)
-#pragma clang diagnostic ignored "-Wreserved-user-defined-literal"
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wuser-defined-literals"
-#elif defined(__GNUC__)
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wliteral-suffix"
-#endif // __clang__
-
-#if nssv_COMPILER_MSVC_VERSION >= 140
-#define nssv_SUPPRESS_MSGSL_WARNING(expr) [[gsl::suppress(expr)]]
-#define nssv_SUPPRESS_MSVC_WARNING(code, descr) __pragma(warning(suppress : code))
-#define nssv_DISABLE_MSVC_WARNINGS(codes) __pragma(warning(push)) __pragma(warning(disable : codes))
-#else
-#define nssv_SUPPRESS_MSGSL_WARNING(expr)
-#define nssv_SUPPRESS_MSVC_WARNING(code, descr)
-#define nssv_DISABLE_MSVC_WARNINGS(codes)
-#endif
-
-#if defined(__clang__)
-#define nssv_RESTORE_WARNINGS() _Pragma("clang diagnostic pop")
-#elif defined(__GNUC__)
-#define nssv_RESTORE_WARNINGS() _Pragma("GCC diagnostic pop")
-#elif nssv_COMPILER_MSVC_VERSION >= 140
-#define nssv_RESTORE_WARNINGS() __pragma(warning(pop))
-#else
-#define nssv_RESTORE_WARNINGS()
-#endif
-
-// Suppress the following MSVC (GSL) warnings:
-// - C4455, non-gsl   : 'operator ""sv': literal suffix identifiers that do not
-//                      start with an underscore are reserved
-// - C26472, gsl::t.1 : don't use a static_cast for arithmetic conversions;
-//                      use brace initialization, gsl::narrow_cast or gsl::narow
-// - C26481: gsl::b.1 : don't use pointer arithmetic. Use span instead
-
-nssv_DISABLE_MSVC_WARNINGS(4455 26481 26472)
-    // nssv_DISABLE_CLANG_WARNINGS( "-Wuser-defined-literals" )
-    // nssv_DISABLE_GNUC_WARNINGS( -Wliteral-suffix )
-
-    namespace nonstd {
-  namespace sv_lite {
-
-#if nssv_CPP11_OR_GREATER
-
-  namespace detail {
-
-  // Expect tail call optimization to make length() non-recursive:
-
-  template <typename CharT> inline constexpr std::size_t length(CharT *s, std::size_t result = 0) {
-    return *s == '\0' ? result : length(s + 1, result + 1);
-  }
-
-  } // namespace detail
-
-#endif // nssv_CPP11_OR_GREATER
-
-  template <class CharT, class Traits = std::char_traits<CharT>> class basic_string_view;
-
-  //
-  // basic_string_view:
-  //
-
-  template <class CharT, class Traits /* = std::char_traits<CharT> */
-            >
-  class basic_string_view {
-  public:
-    // Member types:
-
-    typedef Traits traits_type;
-    typedef CharT value_type;
-
-    typedef CharT *pointer;
-    typedef CharT const *const_pointer;
-    typedef CharT &reference;
-    typedef CharT const &const_reference;
-
-    typedef const_pointer iterator;
-    typedef const_pointer const_iterator;
-    typedef std::reverse_iterator<const_iterator> reverse_iterator;
-    typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
-
-    typedef std::size_t size_type;
-    typedef std::ptrdiff_t difference_type;
-
-    // 24.4.2.1 Construction and assignment:
-
-    nssv_constexpr basic_string_view() nssv_noexcept : data_(nssv_nullptr), size_(0) {}
-
-#if nssv_CPP11_OR_GREATER
-    nssv_constexpr basic_string_view(basic_string_view const &other) nssv_noexcept = default;
-#else
-    nssv_constexpr basic_string_view(basic_string_view const &other) nssv_noexcept : data_(other.data_),
-                                                                                     size_(other.size_) {}
-#endif
-
-    nssv_constexpr basic_string_view(CharT const *s, size_type count) nssv_noexcept // non-standard noexcept
-        : data_(s),
-          size_(count) {}
-
-    nssv_constexpr basic_string_view(CharT const *s) nssv_noexcept // non-standard noexcept
-        : data_(s)
-#if nssv_CPP17_OR_GREATER
-        ,
-          size_(Traits::length(s))
-#elif nssv_CPP11_OR_GREATER
-        ,
-          size_(detail::length(s))
-#else
-        ,
-          size_(Traits::length(s))
-#endif
-    {
-    }
-
-    // Assignment:
-
-#if nssv_CPP11_OR_GREATER
-    nssv_constexpr14 basic_string_view &operator=(basic_string_view const &other) nssv_noexcept = default;
-#else
-    nssv_constexpr14 basic_string_view &operator=(basic_string_view const &other) nssv_noexcept {
-      data_ = other.data_;
-      size_ = other.size_;
-      return *this;
-    }
-#endif
-
-    // 24.4.2.2 Iterator support:
-
-    nssv_constexpr const_iterator begin() const nssv_noexcept { return data_; }
-    nssv_constexpr const_iterator end() const nssv_noexcept { return data_ + size_; }
-
-    nssv_constexpr const_iterator cbegin() const nssv_noexcept { return begin(); }
-    nssv_constexpr const_iterator cend() const nssv_noexcept { return end(); }
-
-    nssv_constexpr const_reverse_iterator rbegin() const nssv_noexcept { return const_reverse_iterator(end()); }
-    nssv_constexpr const_reverse_iterator rend() const nssv_noexcept { return const_reverse_iterator(begin()); }
-
-    nssv_constexpr const_reverse_iterator crbegin() const nssv_noexcept { return rbegin(); }
-    nssv_constexpr const_reverse_iterator crend() const nssv_noexcept { return rend(); }
-
-    // 24.4.2.3 Capacity:
-
-    nssv_constexpr size_type size() const nssv_noexcept { return size_; }
-    nssv_constexpr size_type length() const nssv_noexcept { return size_; }
-    nssv_constexpr size_type max_size() const nssv_noexcept { return (std::numeric_limits<size_type>::max)(); }
-
-    // since C++20
-    nssv_nodiscard nssv_constexpr bool empty() const nssv_noexcept { return 0 == size_; }
-
-    // 24.4.2.4 Element access:
-
-    nssv_constexpr const_reference operator[](size_type pos) const { return data_at(pos); }
-
-    nssv_constexpr14 const_reference at(size_type pos) const {
-#if nssv_CONFIG_NO_EXCEPTIONS
-      assert(pos < size());
-#else
-      if (pos >= size()) {
-        throw std::out_of_range("nonstd::string_view::at()");
-      }
-#endif
-      return data_at(pos);
-    }
-
-    nssv_constexpr const_reference front() const { return data_at(0); }
-    nssv_constexpr const_reference back() const { return data_at(size() - 1); }
-
-    nssv_constexpr const_pointer data() const nssv_noexcept { return data_; }
-
-    // 24.4.2.5 Modifiers:
-
-    nssv_constexpr14 void remove_prefix(size_type n) {
-      assert(n <= size());
-      data_ += n;
-      size_ -= n;
-    }
-
-    nssv_constexpr14 void remove_suffix(size_type n) {
-      assert(n <= size());
-      size_ -= n;
-    }
-
-    nssv_constexpr14 void swap(basic_string_view &other) nssv_noexcept {
-      using std::swap;
-      swap(data_, other.data_);
-      swap(size_, other.size_);
-    }
-
-    // 24.4.2.6 String operations:
-
-    size_type copy(CharT *dest, size_type n, size_type pos = 0) const {
-#if nssv_CONFIG_NO_EXCEPTIONS
-      assert(pos <= size());
-#else
-      if (pos > size()) {
-        throw std::out_of_range("nonstd::string_view::copy()");
-      }
-#endif
-      const size_type rlen = (std::min)(n, size() - pos);
-
-      (void)Traits::copy(dest, data() + pos, rlen);
-
-      return rlen;
-    }
-
-    nssv_constexpr14 basic_string_view substr(size_type pos = 0, size_type n = npos) const {
-#if nssv_CONFIG_NO_EXCEPTIONS
-      assert(pos <= size());
-#else
-      if (pos > size()) {
-        throw std::out_of_range("nonstd::string_view::substr()");
-      }
-#endif
-      return basic_string_view(data() + pos, (std::min)(n, size() - pos));
-    }
-
-    // compare(), 6x:
-
-    nssv_constexpr14 int compare(basic_string_view other) const nssv_noexcept // (1)
-    {
-      if (const int result = Traits::compare(data(), other.data(), (std::min)(size(), other.size()))) {
-        return result;
-      }
-
-      return size() == other.size() ? 0 : size() < other.size() ? -1 : 1;
-    }
-
-    nssv_constexpr int compare(size_type pos1, size_type n1, basic_string_view other) const // (2)
-    {
-      return substr(pos1, n1).compare(other);
-    }
-
-    nssv_constexpr int compare(size_type pos1, size_type n1, basic_string_view other, size_type pos2,
-                               size_type n2) const // (3)
-    {
-      return substr(pos1, n1).compare(other.substr(pos2, n2));
-    }
-
-    nssv_constexpr int compare(CharT const *s) const // (4)
-    {
-      return compare(basic_string_view(s));
-    }
-
-    nssv_constexpr int compare(size_type pos1, size_type n1, CharT const *s) const // (5)
-    {
-      return substr(pos1, n1).compare(basic_string_view(s));
-    }
-
-    nssv_constexpr int compare(size_type pos1, size_type n1, CharT const *s, size_type n2) const // (6)
-    {
-      return substr(pos1, n1).compare(basic_string_view(s, n2));
-    }
-
-    // 24.4.2.7 Searching:
-
-    // starts_with(), 3x, since C++20:
-
-    nssv_constexpr bool starts_with(basic_string_view v) const nssv_noexcept // (1)
-    {
-      return size() >= v.size() && compare(0, v.size(), v) == 0;
-    }
-
-    nssv_constexpr bool starts_with(CharT c) const nssv_noexcept // (2)
-    {
-      return starts_with(basic_string_view(&c, 1));
-    }
-
-    nssv_constexpr bool starts_with(CharT const *s) const // (3)
-    {
-      return starts_with(basic_string_view(s));
-    }
-
-    // ends_with(), 3x, since C++20:
-
-    nssv_constexpr bool ends_with(basic_string_view v) const nssv_noexcept // (1)
-    {
-      return size() >= v.size() && compare(size() - v.size(), npos, v) == 0;
-    }
-
-    nssv_constexpr bool ends_with(CharT c) const nssv_noexcept // (2)
-    {
-      return ends_with(basic_string_view(&c, 1));
-    }
-
-    nssv_constexpr bool ends_with(CharT const *s) const // (3)
-    {
-      return ends_with(basic_string_view(s));
-    }
-
-    // find(), 4x:
-
-    nssv_constexpr14 size_type find(basic_string_view v, size_type pos = 0) const nssv_noexcept // (1)
-    {
-      return assert(v.size() == 0 || v.data() != nssv_nullptr),
-             pos >= size() ? npos : to_pos(std::search(cbegin() + pos, cend(), v.cbegin(), v.cend(), Traits::eq));
-    }
-
-    nssv_constexpr14 size_type find(CharT c, size_type pos = 0) const nssv_noexcept // (2)
-    {
-      return find(basic_string_view(&c, 1), pos);
-    }
-
-    nssv_constexpr14 size_type find(CharT const *s, size_type pos, size_type n) const // (3)
-    {
-      return find(basic_string_view(s, n), pos);
-    }
-
-    nssv_constexpr14 size_type find(CharT const *s, size_type pos = 0) const // (4)
-    {
-      return find(basic_string_view(s), pos);
-    }
-
-    // rfind(), 4x:
-
-    nssv_constexpr14 size_type rfind(basic_string_view v, size_type pos = npos) const nssv_noexcept // (1)
-    {
-      if (size() < v.size()) {
-        return npos;
-      }
-
-      if (v.empty()) {
-        return (std::min)(size(), pos);
-      }
-
-      const_iterator last = cbegin() + (std::min)(size() - v.size(), pos) + v.size();
-      const_iterator result = std::find_end(cbegin(), last, v.cbegin(), v.cend(), Traits::eq);
-
-      return result != last ? size_type(result - cbegin()) : npos;
-    }
-
-    nssv_constexpr14 size_type rfind(CharT c, size_type pos = npos) const nssv_noexcept // (2)
-    {
-      return rfind(basic_string_view(&c, 1), pos);
-    }
-
-    nssv_constexpr14 size_type rfind(CharT const *s, size_type pos, size_type n) const // (3)
-    {
-      return rfind(basic_string_view(s, n), pos);
-    }
-
-    nssv_constexpr14 size_type rfind(CharT const *s, size_type pos = npos) const // (4)
-    {
-      return rfind(basic_string_view(s), pos);
-    }
-
-    // find_first_of(), 4x:
-
-    nssv_constexpr size_type find_first_of(basic_string_view v, size_type pos = 0) const nssv_noexcept // (1)
-    {
-      return pos >= size() ? npos
-                           : to_pos(std::find_first_of(cbegin() + pos, cend(), v.cbegin(), v.cend(), Traits::eq));
-    }
-
-    nssv_constexpr size_type find_first_of(CharT c, size_type pos = 0) const nssv_noexcept // (2)
-    {
-      return find_first_of(basic_string_view(&c, 1), pos);
-    }
-
-    nssv_constexpr size_type find_first_of(CharT const *s, size_type pos, size_type n) const // (3)
-    {
-      return find_first_of(basic_string_view(s, n), pos);
-    }
-
-    nssv_constexpr size_type find_first_of(CharT const *s, size_type pos = 0) const // (4)
-    {
-      return find_first_of(basic_string_view(s), pos);
-    }
-
-    // find_last_of(), 4x:
-
-    nssv_constexpr size_type find_last_of(basic_string_view v, size_type pos = npos) const nssv_noexcept // (1)
-    {
-      return empty() ? npos
-                     : pos >= size() ? find_last_of(v, size() - 1)
-                                     : to_pos(std::find_first_of(const_reverse_iterator(cbegin() + pos + 1), crend(),
-                                                                 v.cbegin(), v.cend(), Traits::eq));
-    }
-
-    nssv_constexpr size_type find_last_of(CharT c, size_type pos = npos) const nssv_noexcept // (2)
-    {
-      return find_last_of(basic_string_view(&c, 1), pos);
-    }
-
-    nssv_constexpr size_type find_last_of(CharT const *s, size_type pos, size_type count) const // (3)
-    {
-      return find_last_of(basic_string_view(s, count), pos);
-    }
-
-    nssv_constexpr size_type find_last_of(CharT const *s, size_type pos = npos) const // (4)
-    {
-      return find_last_of(basic_string_view(s), pos);
-    }
-
-    // find_first_not_of(), 4x:
-
-    nssv_constexpr size_type find_first_not_of(basic_string_view v, size_type pos = 0) const nssv_noexcept // (1)
-    {
-      return pos >= size() ? npos : to_pos(std::find_if(cbegin() + pos, cend(), not_in_view(v)));
-    }
-
-    nssv_constexpr size_type find_first_not_of(CharT c, size_type pos = 0) const nssv_noexcept // (2)
-    {
-      return find_first_not_of(basic_string_view(&c, 1), pos);
-    }
-
-    nssv_constexpr size_type find_first_not_of(CharT const *s, size_type pos, size_type count) const // (3)
-    {
-      return find_first_not_of(basic_string_view(s, count), pos);
-    }
-
-    nssv_constexpr size_type find_first_not_of(CharT const *s, size_type pos = 0) const // (4)
-    {
-      return find_first_not_of(basic_string_view(s), pos);
-    }
-
-    // find_last_not_of(), 4x:
-
-    nssv_constexpr size_type find_last_not_of(basic_string_view v, size_type pos = npos) const nssv_noexcept // (1)
-    {
-      return empty() ? npos
-                     : pos >= size()
-                           ? find_last_not_of(v, size() - 1)
-                           : to_pos(std::find_if(const_reverse_iterator(cbegin() + pos + 1), crend(), not_in_view(v)));
-    }
-
-    nssv_constexpr size_type find_last_not_of(CharT c, size_type pos = npos) const nssv_noexcept // (2)
-    {
-      return find_last_not_of(basic_string_view(&c, 1), pos);
-    }
-
-    nssv_constexpr size_type find_last_not_of(CharT const *s, size_type pos, size_type count) const // (3)
-    {
-      return find_last_not_of(basic_string_view(s, count), pos);
-    }
-
-    nssv_constexpr size_type find_last_not_of(CharT const *s, size_type pos = npos) const // (4)
-    {
-      return find_last_not_of(basic_string_view(s), pos);
-    }
-
-    // Constants:
-
-#if nssv_CPP17_OR_GREATER
-    static nssv_constexpr size_type npos = size_type(-1);
-#elif nssv_CPP11_OR_GREATER
-    enum : size_type { npos = size_type(-1) };
-#else
-    enum { npos = size_type(-1) };
-#endif
-
-  private:
-    struct not_in_view {
-      const basic_string_view v;
-
-      nssv_constexpr explicit not_in_view(basic_string_view v) : v(v) {}
-
-      nssv_constexpr bool operator()(CharT c) const { return npos == v.find_first_of(c); }
-    };
-
-    nssv_constexpr size_type to_pos(const_iterator it) const { return it == cend() ? npos : size_type(it - cbegin()); }
-
-    nssv_constexpr size_type to_pos(const_reverse_iterator it) const {
-      return it == crend() ? npos : size_type(crend() - it - 1);
-    }
-
-    nssv_constexpr const_reference data_at(size_type pos) const {
-#if nssv_BETWEEN(nssv_COMPILER_GNUC_VERSION, 1, 500)
-      return data_[pos];
-#else
-      return assert(pos < size()), data_[pos];
-#endif
-    }
-
-  private:
-    const_pointer data_;
-    size_type size_;
-
-  public:
-#if nssv_CONFIG_CONVERSION_STD_STRING_CLASS_METHODS
-
-    template <class Allocator>
-    basic_string_view(std::basic_string<CharT, Traits, Allocator> const &s) nssv_noexcept : data_(s.data()),
-                                                                                            size_(s.size()) {}
-
-#if nssv_HAVE_EXPLICIT_CONVERSION
-
-    template <class Allocator> explicit operator std::basic_string<CharT, Traits, Allocator>() const {
-      return to_string(Allocator());
-    }
-
-#endif // nssv_HAVE_EXPLICIT_CONVERSION
-
-#if nssv_CPP11_OR_GREATER
-
-    template <class Allocator = std::allocator<CharT>>
-    std::basic_string<CharT, Traits, Allocator> to_string(Allocator const &a = Allocator()) const {
-      return std::basic_string<CharT, Traits, Allocator>(begin(), end(), a);
-    }
-
-#else
-
-    std::basic_string<CharT, Traits> to_string() const { return std::basic_string<CharT, Traits>(begin(), end()); }
-
-    template <class Allocator> std::basic_string<CharT, Traits, Allocator> to_string(Allocator const &a) const {
-      return std::basic_string<CharT, Traits, Allocator>(begin(), end(), a);
-    }
-
-#endif // nssv_CPP11_OR_GREATER
-
-#endif // nssv_CONFIG_CONVERSION_STD_STRING_CLASS_METHODS
-  };
-
-  //
-  // Non-member functions:
-  //
-
-  // 24.4.3 Non-member comparison functions:
-  // lexicographically compare two string views (function template):
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator==(basic_string_view<CharT, Traits> lhs,
-                                 basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) == 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator!=(basic_string_view<CharT, Traits> lhs,
-                                 basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) != 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<(basic_string_view<CharT, Traits> lhs,
-                                basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) < 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<=(basic_string_view<CharT, Traits> lhs,
-                                 basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) <= 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>(basic_string_view<CharT, Traits> lhs,
-                                basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) > 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>=(basic_string_view<CharT, Traits> lhs,
-                                 basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) >= 0;
-  }
-
-  // Let S be basic_string_view<CharT, Traits>, and sv be an instance of S.
-  // Implementations shall provide sufficient additional overloads marked
-  // constexpr and noexcept so that an object t with an implicit conversion
-  // to S can be compared according to Table 67.
-
-#if !nssv_CPP11_OR_GREATER || nssv_BETWEEN(nssv_COMPILER_MSVC_VERSION, 100, 141)
-
-  // accomodate for older compilers:
-
-  // ==
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator==(basic_string_view<CharT, Traits> lhs, char const *rhs) nssv_noexcept {
-    return lhs.compare(rhs) == 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator==(char const *lhs, basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return rhs.compare(lhs) == 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator==(basic_string_view<CharT, Traits> lhs,
-                                 std::basic_string<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.size() == rhs.size() && lhs.compare(rhs) == 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator==(std::basic_string<CharT, Traits> rhs,
-                                 basic_string_view<CharT, Traits> lhs) nssv_noexcept {
-    return lhs.size() == rhs.size() && lhs.compare(rhs) == 0;
-  }
-
-  // !=
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator!=(basic_string_view<CharT, Traits> lhs, char const *rhs) nssv_noexcept {
-    return lhs.compare(rhs) != 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator!=(char const *lhs, basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return rhs.compare(lhs) != 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator!=(basic_string_view<CharT, Traits> lhs,
-                                 std::basic_string<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.size() != rhs.size() && lhs.compare(rhs) != 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator!=(std::basic_string<CharT, Traits> rhs,
-                                 basic_string_view<CharT, Traits> lhs) nssv_noexcept {
-    return lhs.size() != rhs.size() || rhs.compare(lhs) != 0;
-  }
-
-  // <
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<(basic_string_view<CharT, Traits> lhs, char const *rhs) nssv_noexcept {
-    return lhs.compare(rhs) < 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<(char const *lhs, basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return rhs.compare(lhs) > 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<(basic_string_view<CharT, Traits> lhs,
-                                std::basic_string<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) < 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<(std::basic_string<CharT, Traits> rhs,
-                                basic_string_view<CharT, Traits> lhs) nssv_noexcept {
-    return rhs.compare(lhs) > 0;
-  }
-
-  // <=
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<=(basic_string_view<CharT, Traits> lhs, char const *rhs) nssv_noexcept {
-    return lhs.compare(rhs) <= 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<=(char const *lhs, basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return rhs.compare(lhs) >= 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<=(basic_string_view<CharT, Traits> lhs,
-                                 std::basic_string<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) <= 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator<=(std::basic_string<CharT, Traits> rhs,
-                                 basic_string_view<CharT, Traits> lhs) nssv_noexcept {
-    return rhs.compare(lhs) >= 0;
-  }
-
-  // >
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>(basic_string_view<CharT, Traits> lhs, char const *rhs) nssv_noexcept {
-    return lhs.compare(rhs) > 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>(char const *lhs, basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return rhs.compare(lhs) < 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>(basic_string_view<CharT, Traits> lhs,
-                                std::basic_string<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) > 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>(std::basic_string<CharT, Traits> rhs,
-                                basic_string_view<CharT, Traits> lhs) nssv_noexcept {
-    return rhs.compare(lhs) < 0;
-  }
-
-  // >=
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>=(basic_string_view<CharT, Traits> lhs, char const *rhs) nssv_noexcept {
-    return lhs.compare(rhs) >= 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>=(char const *lhs, basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return rhs.compare(lhs) <= 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>=(basic_string_view<CharT, Traits> lhs,
-                                 std::basic_string<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) >= 0;
-  }
-
-  template <class CharT, class Traits>
-  nssv_constexpr bool operator>=(std::basic_string<CharT, Traits> rhs,
-                                 basic_string_view<CharT, Traits> lhs) nssv_noexcept {
-    return rhs.compare(lhs) <= 0;
-  }
-
-#else // newer compilers:
-
-#define nssv_BASIC_STRING_VIEW_I(T, U) typename std::decay<basic_string_view<T, U>>::type
-
-#if nssv_BETWEEN(nssv_COMPILER_MSVC_VERSION, 140, 150)
-#define nssv_MSVC_ORDER(x) , int = x
-#else
-#define nssv_MSVC_ORDER(x) /*, int=x*/
-#endif
-
-  // ==
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(1)>
-  nssv_constexpr bool operator==(basic_string_view<CharT, Traits> lhs,
-                                 nssv_BASIC_STRING_VIEW_I(CharT, Traits) rhs) nssv_noexcept {
-    return lhs.compare(rhs) == 0;
-  }
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(2)>
-  nssv_constexpr bool operator==(nssv_BASIC_STRING_VIEW_I(CharT, Traits) lhs,
-                                 basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.size() == rhs.size() && lhs.compare(rhs) == 0;
-  }
-
-  // !=
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(1)>
-  nssv_constexpr bool operator!=(basic_string_view<CharT, Traits> lhs,
-                                 nssv_BASIC_STRING_VIEW_I(CharT, Traits) rhs) nssv_noexcept {
-    return lhs.size() != rhs.size() || lhs.compare(rhs) != 0;
-  }
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(2)>
-  nssv_constexpr bool operator!=(nssv_BASIC_STRING_VIEW_I(CharT, Traits) lhs,
-                                 basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) != 0;
-  }
-
-  // <
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(1)>
-  nssv_constexpr bool operator<(basic_string_view<CharT, Traits> lhs,
-                                nssv_BASIC_STRING_VIEW_I(CharT, Traits) rhs) nssv_noexcept {
-    return lhs.compare(rhs) < 0;
-  }
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(2)>
-  nssv_constexpr bool operator<(nssv_BASIC_STRING_VIEW_I(CharT, Traits) lhs,
-                                basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) < 0;
-  }
-
-  // <=
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(1)>
-  nssv_constexpr bool operator<=(basic_string_view<CharT, Traits> lhs,
-                                 nssv_BASIC_STRING_VIEW_I(CharT, Traits) rhs) nssv_noexcept {
-    return lhs.compare(rhs) <= 0;
-  }
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(2)>
-  nssv_constexpr bool operator<=(nssv_BASIC_STRING_VIEW_I(CharT, Traits) lhs,
-                                 basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) <= 0;
-  }
-
-  // >
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(1)>
-  nssv_constexpr bool operator>(basic_string_view<CharT, Traits> lhs,
-                                nssv_BASIC_STRING_VIEW_I(CharT, Traits) rhs) nssv_noexcept {
-    return lhs.compare(rhs) > 0;
-  }
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(2)>
-  nssv_constexpr bool operator>(nssv_BASIC_STRING_VIEW_I(CharT, Traits) lhs,
-                                basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) > 0;
-  }
-
-  // >=
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(1)>
-  nssv_constexpr bool operator>=(basic_string_view<CharT, Traits> lhs,
-                                 nssv_BASIC_STRING_VIEW_I(CharT, Traits) rhs) nssv_noexcept {
-    return lhs.compare(rhs) >= 0;
-  }
-
-  template <class CharT, class Traits nssv_MSVC_ORDER(2)>
-  nssv_constexpr bool operator>=(nssv_BASIC_STRING_VIEW_I(CharT, Traits) lhs,
-                                 basic_string_view<CharT, Traits> rhs) nssv_noexcept {
-    return lhs.compare(rhs) >= 0;
-  }
-
-#undef nssv_MSVC_ORDER
-#undef nssv_BASIC_STRING_VIEW_I
-
-#endif // compiler-dependent approach to comparisons
-
-  // 24.4.4 Inserters and extractors:
-
-  namespace detail {
-
-  template <class Stream> void write_padding(Stream &os, std::streamsize n) {
-    for (std::streamsize i = 0; i < n; ++i)
-      os.rdbuf()->sputc(os.fill());
-  }
-
-  template <class Stream, class View> Stream &write_to_stream(Stream &os, View const &sv) {
-    typename Stream::sentry sentry(os);
-
-    if (!os)
-      return os;
-
-    const std::streamsize length = static_cast<std::streamsize>(sv.length());
-
-    // Whether, and how, to pad:
-    const bool pad = (length < os.width());
-    const bool left_pad = pad && (os.flags() & std::ios_base::adjustfield) == std::ios_base::right;
-
-    if (left_pad)
-      write_padding(os, os.width() - length);
-
-    // Write span characters:
-    os.rdbuf()->sputn(sv.begin(), length);
-
-    if (pad && !left_pad)
-      write_padding(os, os.width() - length);
-
-    // Reset output stream width:
-    os.width(0);
-
-    return os;
-  }
-
-  } // namespace detail
-
-  template <class CharT, class Traits>
-  std::basic_ostream<CharT, Traits> &operator<<(std::basic_ostream<CharT, Traits> &os,
-                                                basic_string_view<CharT, Traits> sv) {
-    return detail::write_to_stream(os, sv);
-  }
-
-  // Several typedefs for common character types are provided:
-
-  typedef basic_string_view<char> string_view;
-  typedef basic_string_view<wchar_t> wstring_view;
-#if nssv_HAVE_WCHAR16_T
-  typedef basic_string_view<char16_t> u16string_view;
-  typedef basic_string_view<char32_t> u32string_view;
-#endif
-
-  } // namespace sv_lite
-} // namespace nonstd::sv_lite
-
-//
-// 24.4.6 Suffix for basic_string_view literals:
-//
-
-#if nssv_HAVE_USER_DEFINED_LITERALS
-
-namespace nonstd {
-nssv_inline_ns namespace literals {
-  nssv_inline_ns namespace string_view_literals {
-
-#if nssv_CONFIG_STD_SV_OPERATOR && nssv_HAVE_STD_DEFINED_LITERALS
-
-    nssv_constexpr nonstd::sv_lite::string_view operator"" sv(const char *str, size_t len) nssv_noexcept // (1)
-    {
-      return nonstd::sv_lite::string_view {str, len};
-    }
-
-    nssv_constexpr nonstd::sv_lite::u16string_view operator"" sv(const char16_t *str, size_t len) nssv_noexcept // (2)
-    {
-      return nonstd::sv_lite::u16string_view {str, len};
-    }
-
-    nssv_constexpr nonstd::sv_lite::u32string_view operator"" sv(const char32_t *str, size_t len) nssv_noexcept // (3)
-    {
-      return nonstd::sv_lite::u32string_view {str, len};
-    }
-
-    nssv_constexpr nonstd::sv_lite::wstring_view operator"" sv(const wchar_t *str, size_t len) nssv_noexcept // (4)
-    {
-      return nonstd::sv_lite::wstring_view {str, len};
-    }
-
-#endif // nssv_CONFIG_STD_SV_OPERATOR && nssv_HAVE_STD_DEFINED_LITERALS
-
-#if nssv_CONFIG_USR_SV_OPERATOR
-
-    nssv_constexpr nonstd::sv_lite::string_view operator"" _sv(const char *str, size_t len) nssv_noexcept // (1)
-    {
-      return nonstd::sv_lite::string_view {str, len};
-    }
-
-    nssv_constexpr nonstd::sv_lite::u16string_view operator"" _sv(const char16_t *str, size_t len) nssv_noexcept // (2)
-    {
-      return nonstd::sv_lite::u16string_view {str, len};
-    }
-
-    nssv_constexpr nonstd::sv_lite::u32string_view operator"" _sv(const char32_t *str, size_t len) nssv_noexcept // (3)
-    {
-      return nonstd::sv_lite::u32string_view {str, len};
-    }
-
-    nssv_constexpr nonstd::sv_lite::wstring_view operator"" _sv(const wchar_t *str, size_t len) nssv_noexcept // (4)
-    {
-      return nonstd::sv_lite::wstring_view {str, len};
-    }
-
-#endif // nssv_CONFIG_USR_SV_OPERATOR
-  }
-}
-} // namespace nonstd
-
-#endif
-
-//
-// Extensions for std::string:
-//
-
-#if nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS
-
-namespace nonstd {
-namespace sv_lite {
-
-// Exclude MSVC 14 (19.00): it yields ambiguous to_string():
-
-#if nssv_CPP11_OR_GREATER && nssv_COMPILER_MSVC_VERSION != 140
-
-template <class CharT, class Traits, class Allocator = std::allocator<CharT>>
-std::basic_string<CharT, Traits, Allocator> to_string(basic_string_view<CharT, Traits> v,
-                                                      Allocator const &a = Allocator()) {
-  return std::basic_string<CharT, Traits, Allocator>(v.begin(), v.end(), a);
-}
-
-#else
-
-template <class CharT, class Traits> std::basic_string<CharT, Traits> to_string(basic_string_view<CharT, Traits> v) {
-  return std::basic_string<CharT, Traits>(v.begin(), v.end());
-}
-
-template <class CharT, class Traits, class Allocator>
-std::basic_string<CharT, Traits, Allocator> to_string(basic_string_view<CharT, Traits> v, Allocator const &a) {
-  return std::basic_string<CharT, Traits, Allocator>(v.begin(), v.end(), a);
-}
-
-#endif // nssv_CPP11_OR_GREATER
-
-template <class CharT, class Traits, class Allocator>
-basic_string_view<CharT, Traits> to_string_view(std::basic_string<CharT, Traits, Allocator> const &s) {
-  return basic_string_view<CharT, Traits>(s.data(), s.size());
-}
-
-} // namespace sv_lite
-} // namespace nonstd
-
-#endif // nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS
-
-//
-// make types and algorithms available in namespace nonstd:
-//
-
-namespace nonstd {
-
-using sv_lite::basic_string_view;
-using sv_lite::string_view;
-using sv_lite::wstring_view;
-
-#if nssv_HAVE_WCHAR16_T
-using sv_lite::u16string_view;
-#endif
-#if nssv_HAVE_WCHAR32_T
-using sv_lite::u32string_view;
-#endif
-
-// literal "sv"
-
-using sv_lite::operator==;
-using sv_lite::operator!=;
-using sv_lite::operator<;
-using sv_lite::operator<=;
-using sv_lite::operator>;
-using sv_lite::operator>=;
-
-using sv_lite::operator<<;
-
-#if nssv_CONFIG_CONVERSION_STD_STRING_FREE_FUNCTIONS
-using sv_lite::to_string;
-using sv_lite::to_string_view;
-#endif
-
-} // namespace nonstd
-
-// 24.4.5 Hash support (C++11):
-
-// Note: The hash value of a string view object is equal to the hash value of
-// the corresponding string object.
-
-#if nssv_HAVE_STD_HASH
-
-#include <functional>
-
-namespace std {
-
-template <> struct hash<nonstd::string_view> {
-public:
-  std::size_t operator()(nonstd::string_view v) const nssv_noexcept {
-    return std::hash<std::string>()(std::string(v.data(), v.size()));
-  }
-};
-
-template <> struct hash<nonstd::wstring_view> {
-public:
-  std::size_t operator()(nonstd::wstring_view v) const nssv_noexcept {
-    return std::hash<std::wstring>()(std::wstring(v.data(), v.size()));
-  }
-};
-
-template <> struct hash<nonstd::u16string_view> {
-public:
-  std::size_t operator()(nonstd::u16string_view v) const nssv_noexcept {
-    return std::hash<std::u16string>()(std::u16string(v.data(), v.size()));
-  }
-};
-
-template <> struct hash<nonstd::u32string_view> {
-public:
-  std::size_t operator()(nonstd::u32string_view v) const nssv_noexcept {
-    return std::hash<std::u32string>()(std::u32string(v.data(), v.size()));
-  }
-};
-
-} // namespace std
-
-#endif // nssv_HAVE_STD_HASH
-
-nssv_RESTORE_WARNINGS()
-
-#endif // nssv_HAVE_STD_STRING_VIEW
-#endif // NONSTD_SV_LITE_H_INCLUDED
-
 // #include "template.hpp"
 #ifndef INCLUDE_INJA_TEMPLATE_HPP_
 #define INCLUDE_INJA_TEMPLATE_HPP_
@@ -1498,16 +81,16 @@
 #define INCLUDE_INJA_NODE_HPP_
 
 #include <string>
+#include <string_view>
 #include <utility>
 
 // #include "function_storage.hpp"
 #ifndef INCLUDE_INJA_FUNCTION_STORAGE_HPP_
 #define INCLUDE_INJA_FUNCTION_STORAGE_HPP_
 
+#include <string_view>
 #include <vector>
 
-// #include "string_view.hpp"
-
 
 namespace inja {
 
@@ -1614,15 +197,15 @@
   };
 
 public:
-  void add_builtin(nonstd::string_view name, int num_args, Operation op) {
+  void add_builtin(std::string_view name, int num_args, Operation op) {
     function_storage.emplace(std::make_pair(static_cast<std::string>(name), num_args), FunctionData { op });
   }
 
-  void add_callback(nonstd::string_view name, int num_args, const CallbackFunction &callback) {
+  void add_callback(std::string_view name, int num_args, const CallbackFunction &callback) {
     function_storage.emplace(std::make_pair(static_cast<std::string>(name), num_args), FunctionData { Operation::Callback, callback });
   }
 
-  FunctionData find_function(nonstd::string_view name, int num_args) const {
+  FunctionData find_function(std::string_view name, int num_args) const {
     auto it = function_storage.find(std::make_pair(static_cast<std::string>(name), num_args));
     if (it != function_storage.end()) {
       return it->second;
@@ -1643,8 +226,6 @@
 
 #endif // INCLUDE_INJA_FUNCTION_STORAGE_HPP_
 
-// #include "string_view.hpp"
-
 // #include "utils.hpp"
 #ifndef INCLUDE_INJA_UTILS_HPP_
 #define INCLUDE_INJA_UTILS_HPP_
@@ -1652,6 +233,7 @@
 #include <algorithm>
 #include <fstream>
 #include <string>
+#include <string_view>
 #include <utility>
 
 // #include "exceptions.hpp"
@@ -1704,37 +286,36 @@
 
 #endif // INCLUDE_INJA_EXCEPTIONS_HPP_
 
-// #include "string_view.hpp"
 
 
 namespace inja {
 
 namespace string_view {
-inline nonstd::string_view slice(nonstd::string_view view, size_t start, size_t end) {
+inline std::string_view slice(std::string_view view, size_t start, size_t end) {
   start = std::min(start, view.size());
   end = std::min(std::max(start, end), view.size());
   return view.substr(start, end - start);
 }
 
-inline std::pair<nonstd::string_view, nonstd::string_view> split(nonstd::string_view view, char Separator) {
+inline std::pair<std::string_view, std::string_view> split(std::string_view view, char Separator) {
   size_t idx = view.find(Separator);
-  if (idx == nonstd::string_view::npos) {
-    return std::make_pair(view, nonstd::string_view());
+  if (idx == std::string_view::npos) {
+    return std::make_pair(view, std::string_view());
   }
-  return std::make_pair(slice(view, 0, idx), slice(view, idx + 1, nonstd::string_view::npos));
+  return std::make_pair(slice(view, 0, idx), slice(view, idx + 1, std::string_view::npos));
 }
 
-inline bool starts_with(nonstd::string_view view, nonstd::string_view prefix) {
+inline bool starts_with(std::string_view view, std::string_view prefix) {
   return (view.size() >= prefix.size() && view.compare(0, prefix.size(), prefix) == 0);
 }
 } // namespace string_view
 
-inline SourceLocation get_source_location(nonstd::string_view content, size_t pos) {
+inline SourceLocation get_source_location(std::string_view content, size_t pos) {
   // Get line and offset position (starts at 1:1)
   auto sliced = string_view::slice(content, 0, pos);
   std::size_t last_newline = sliced.rfind("\n");
 
-  if (last_newline == nonstd::string_view::npos) {
+  if (last_newline == std::string_view::npos) {
     return {1, sliced.length() + 1};
   }
 
@@ -1873,10 +454,10 @@
   const std::string name;
   const json::json_pointer ptr;
 
-  static std::string convert_dot_to_json_ptr(nonstd::string_view ptr_name) {
+  static std::string convert_dot_to_json_ptr(std::string_view ptr_name) {
     std::string result;
     do {
-      nonstd::string_view part;
+      std::string_view part;
       std::tie(part, ptr_name) = string_view::split(ptr_name, '.');
       result.push_back('/');
       result.append(part.begin(), part.end());
@@ -1884,7 +465,7 @@
     return result;
   }
 
-  explicit JsonNode(nonstd::string_view ptr_name, size_t pos) : ExpressionNode(pos), name(ptr_name), ptr(json::json_pointer(convert_dot_to_json_ptr(ptr_name))) { }
+  explicit JsonNode(std::string_view ptr_name, size_t pos) : ExpressionNode(pos), name(ptr_name), ptr(json::json_pointer(convert_dot_to_json_ptr(ptr_name))) { }
 
   void accept(NodeVisitor& v) const {
     v.visit(*this);
@@ -1910,7 +491,7 @@
   std::vector<std::shared_ptr<ExpressionNode>> arguments;
   CallbackFunction callback;
 
-  explicit FunctionNode(nonstd::string_view name, size_t pos) : ExpressionNode(pos), precedence(8), associativity(Associativity::Left), operation(Op::Callback), name(name), number_args(1) { }
+  explicit FunctionNode(std::string_view name, size_t pos) : ExpressionNode(pos), precedence(8), associativity(Associativity::Left), operation(Op::Callback), name(name), number_args(1) { }
   explicit FunctionNode(Op operation, size_t pos) : ExpressionNode(pos), operation(operation), number_args(1) {
     switch (operation) {
       case Op::Not: {
@@ -2346,8 +927,7 @@
 #define INCLUDE_INJA_TOKEN_HPP_
 
 #include <string>
-
-// #include "string_view.hpp"
+#include <string_view>
 
 
 namespace inja {
@@ -2395,10 +975,10 @@
   };
   
   Kind kind {Kind::Unknown};
-  nonstd::string_view text;
+  std::string_view text;
 
   explicit constexpr Token() = default;
-  explicit constexpr Token(Kind kind, nonstd::string_view text) : kind(kind), text(text) {}
+  explicit constexpr Token(Kind kind, std::string_view text) : kind(kind), text(text) {}
 
   std::string describe() const {
     switch (kind) {
@@ -2452,12 +1032,12 @@
 
   State state;
   MinusState minus_state;
-  nonstd::string_view m_in;
+  std::string_view m_in;
   size_t tok_start;
   size_t pos;
 
 
-  Token scan_body(nonstd::string_view close, Token::Kind closeKind, nonstd::string_view close_trim = nonstd::string_view(), bool trim = false) {
+  Token scan_body(std::string_view close, Token::Kind closeKind, std::string_view close_trim = std::string_view(), bool trim = false) {
   again:
     // skip whitespace (except for \n as it might be a close)
     if (tok_start >= m_in.size()) {
@@ -2667,8 +1247,8 @@
     }
   }
 
-  static nonstd::string_view clear_final_line_if_whitespace(nonstd::string_view text) {
-    nonstd::string_view result = text;
+  static std::string_view clear_final_line_if_whitespace(std::string_view text) {
+    std::string_view result = text;
     while (!result.empty()) {
       const char ch = result.back();
       if (ch == ' ' || ch == '\t') {
@@ -2689,7 +1269,7 @@
     return get_source_location(m_in, tok_start);
   }
 
-  void start(nonstd::string_view input) {
+  void start(std::string_view input) {
     m_in = input;
     tok_start = 0;
     pos = 0;
@@ -2715,7 +1295,7 @@
     case State::Text: {
       // fast-scan to first open character
       const size_t open_start = m_in.substr(pos).find_first_of(config.open_chars);
-      if (open_start == nonstd::string_view::npos) {
+      if (open_start == std::string_view::npos) {
         // didn't find open, return remaining text as text token
         pos = m_in.size();
         return make_token(Token::Kind::Text);
@@ -2723,7 +1303,7 @@
       pos += open_start;
 
       // try to match one of the opening sequences, and get the close
-      nonstd::string_view open_str = m_in.substr(pos);
+      std::string_view open_str = m_in.substr(pos);
       bool must_lstrip = false;
       if (inja::string_view::starts_with(open_str, config.expression_open)) {
         if (inja::string_view::starts_with(open_str, config.expression_open_force_lstrip)) {
@@ -2757,7 +1337,7 @@
         goto again;
       }
 
-      nonstd::string_view text = string_view::slice(m_in, tok_start, pos);
+      std::string_view text = string_view::slice(m_in, tok_start, pos);
       if (must_lstrip) {
         text = clear_final_line_if_whitespace(text);
       }
@@ -2816,7 +1396,7 @@
     case State::CommentBody: {
       // fast-scan to comment close
       const size_t end = m_in.substr(pos).find(config.comment_close);
-      if (end == nonstd::string_view::npos) {
+      if (end == std::string_view::npos) {
         pos = m_in.size();
         return make_token(Token::Kind::Eof);
       }
@@ -2875,7 +1455,7 @@
   size_t current_bracket_level {0};
   size_t current_brace_level {0};
 
-  nonstd::string_view json_literal_start;
+  std::string_view json_literal_start;
 
   BlockNode *current_block {nullptr};
   ExpressionListNode *current_expression_list {nullptr};
@@ -2908,7 +1488,7 @@
   }
 
   inline void add_json_literal(const char* content_ptr) {
-    nonstd::string_view json_text(json_literal_start.data(), tok.text.data() - json_literal_start.data() + tok.text.size());
+    std::string_view json_text(json_literal_start.data(), tok.text.data() - json_literal_start.data() + tok.text.size());
     arguments.emplace_back(std::make_shared<LiteralNode>(json::parse(json_text), json_text.data() - content_ptr));
   }
 
@@ -2923,7 +1503,7 @@
     arguments.emplace_back(function);
   }
 
-  void add_to_template_storage(nonstd::string_view path, std::string& template_name) {
+  void add_to_template_storage(std::string_view path, std::string& template_name) {
     if (template_storage.find(template_name) != template_storage.end()) {
       return;
     }
@@ -3204,7 +1784,7 @@
     return true;
   }
 
-  bool parse_statement(Template &tmpl, Token::Kind closing, nonstd::string_view path) {
+  bool parse_statement(Template &tmpl, Token::Kind closing, std::string_view path) {
     if (tok.kind != Token::Kind::Id) {
       return false;
     }
@@ -3406,7 +1986,7 @@
     return true;
   }
 
-  void parse_into(Template &tmpl, nonstd::string_view path) {
+  void parse_into(Template &tmpl, std::string_view path) {
     lexer.start(tmpl.content);
     current_block = &tmpl.root;
 
@@ -3476,18 +2056,18 @@
                   TemplateStorage &template_storage, const FunctionStorage &function_storage)
       : config(parser_config), lexer(lexer_config), template_storage(template_storage), function_storage(function_storage) { }
 
-  Template parse(nonstd::string_view input, nonstd::string_view path) {
+  Template parse(std::string_view input, std::string_view path) {
     auto result = Template(static_cast<std::string>(input));
     parse_into(result, path);
     return result;
   }
 
-  Template parse(nonstd::string_view input) {
+  Template parse(std::string_view input) {
     return parse(input, "./");
   }
 
-  void parse_into_template(Template& tmpl, nonstd::string_view filename) {
-    nonstd::string_view path = filename.substr(0, filename.find_last_of("/\\") + 1);
+  void parse_into_template(Template& tmpl, std::string_view filename) {
+    std::string_view path = filename.substr(0, filename.find_last_of("/\\") + 1);
 
     // StringRef path = sys::path::parent_path(filename);
     auto sub_parser = Parser(config, lexer.get_config(), template_storage, function_storage);
@@ -4231,8 +2811,6 @@
 
 #endif // INCLUDE_INJA_RENDERER_HPP_
 
-// #include "string_view.hpp"
-
 // #include "template.hpp"
 
 // #include "utils.hpp"
@@ -4316,7 +2894,7 @@
     render_config.throw_at_missing_includes = will_throw;
   }
 
-  Template parse(nonstd::string_view input) {
+  Template parse(std::string_view input) {
     Parser parser(parser_config, lexer_config, template_storage, function_storage);
     return parser.parse(input);
   }
@@ -4332,7 +2910,7 @@
     return parse_template(filename);
   }
 
-  std::string render(nonstd::string_view input, const json &data) { return render(parse(input), data); }
+  std::string render(std::string_view input, const json &data) { return render(parse(input), data); }
 
   std::string render(const Template &tmpl, const json &data) {
     std::stringstream os;
@@ -4440,14 +3018,14 @@
 /*!
 @brief render with default settings to a string
 */
-inline std::string render(nonstd::string_view input, const json &data) {
+inline std::string render(std::string_view input, const json &data) {
   return Environment().render(input, data);
 }
 
 /*!
 @brief render with default settings to the given output stream
 */
-inline void render_to(std::ostream &os, nonstd::string_view input, const json &data) {
+inline void render_to(std::ostream &os, std::string_view input, const json &data) {
   Environment env;
   env.render_to(os, env.parse(input), data);
 }
@@ -4462,8 +3040,6 @@
 
 // #include "renderer.hpp"
 
-// #include "string_view.hpp"
-
 // #include "template.hpp"