Fixes #340: namespace indentation unification (#350)

* Namespace no longer induce indentation
* Namespace opening brace now on same line as namespace name
* Namespace closing brace now has an empty line before it unless the namespace contents were short and with no empty lines
* Namespace closing brace now always followed by a comment with the closed namespace' name

1 files changed, 1578 insertions, 1584 deletions

diff --git a/include/cxxopts.hpp b/include/cxxopts.hpp
index a335917..4b03093 100644
--- a/include/cxxopts.hpp
+++ b/include/cxxopts.hpp
@@ -79,15 +79,14 @@ THE SOFTWARE.
   #define CXXOPTS_NULL_DEREF_IGNORE
 #endif
 
-namespace cxxopts
-{
-  static constexpr struct {
-    uint8_t major, minor, patch;
-  } version = {
-    CXXOPTS__VERSION_MAJOR,
-    CXXOPTS__VERSION_MINOR,
-    CXXOPTS__VERSION_PATCH
-  };
+namespace cxxopts {
+static constexpr struct {
+  uint8_t major, minor, patch;
+} version = {
+  CXXOPTS__VERSION_MAJOR,
+  CXXOPTS__VERSION_MINOR,
+  CXXOPTS__VERSION_PATCH
+};
 } // namespace cxxopts
 
 //when we ask cxxopts to use Unicode, help strings are processed using ICU,
@@ -99,16 +98,15 @@ namespace cxxopts
 #ifdef CXXOPTS_USE_UNICODE
 #include <unicode/unistr.h>
 
-namespace cxxopts
-{
-  using String = icu::UnicodeString;
+namespace cxxopts {
+using String = icu::UnicodeString;
 
-  inline
-  String
-  toLocalString(std::string s)
-  {
-    return icu::UnicodeString::fromUTF8(std::move(s));
-  }
+inline
+String
+toLocalString(std::string s)
+{
+  return icu::UnicodeString::fromUTF8(std::move(s));
+}
 
 #if defined(__GNUC__)
 // GNU GCC with -Weffc++ will issue a warning regarding the upcoming class, we want to silence it:
@@ -118,202 +116,201 @@ namespace cxxopts
 #pragma GCC diagnostic ignored "-Weffc++"
 // This will be ignored under other compilers like LLVM clang.
 #endif
-  class UnicodeStringIterator : public
-    std::iterator<std::forward_iterator_tag, int32_t>
-  {
-    public:
-
-    UnicodeStringIterator(const icu::UnicodeString* string, int32_t pos)
-    : s(string)
-    , i(pos)
-    {
-    }
-
-    value_type
-    operator*() const
-    {
-      return s->char32At(i);
-    }
-
-    bool
-    operator==(const UnicodeStringIterator& rhs) const
-    {
-      return s == rhs.s && i == rhs.i;
-    }
-
-    bool
-    operator!=(const UnicodeStringIterator& rhs) const
-    {
-      return !(*this == rhs);
-    }
-
-    UnicodeStringIterator&
-    operator++()
-    {
-      ++i;
-      return *this;
-    }
-
-    UnicodeStringIterator
-    operator+(int32_t v)
-    {
-      return UnicodeStringIterator(s, i + v);
-    }
-
-    private:
-    const icu::UnicodeString* s;
-    int32_t i;
-  };
-#if defined(__GNUC__)
-#pragma GCC diagnostic pop
-#endif
+class UnicodeStringIterator : public
+  std::iterator<std::forward_iterator_tag, int32_t>
+{
+  public:
 
-  inline
-  String&
-  stringAppend(String&s, String a)
+  UnicodeStringIterator(const icu::UnicodeString* string, int32_t pos)
+  : s(string)
+  , i(pos)
   {
-    return s.append(std::move(a));
   }
 
-  inline
-  String&
-  stringAppend(String& s, size_t n, UChar32 c)
+  value_type
+  operator*() const
   {
-    for (size_t i = 0; i != n; ++i)
-    {
-      s.append(c);
-    }
-
-    return s;
+    return s->char32At(i);
   }
 
-  template <typename Iterator>
-  String&
-  stringAppend(String& s, Iterator begin, Iterator end)
+  bool
+  operator==(const UnicodeStringIterator& rhs) const
   {
-    while (begin != end)
-    {
-      s.append(*begin);
-      ++begin;
-    }
-
-    return s;
+    return s == rhs.s && i == rhs.i;
   }
 
-  inline
-  size_t
-  stringLength(const String& s)
+  bool
+  operator!=(const UnicodeStringIterator& rhs) const
   {
-    return s.length();
+    return !(*this == rhs);
   }
 
-  inline
-  std::string
-  toUTF8String(const String& s)
+  UnicodeStringIterator&
+  operator++()
   {
-    std::string result;
-    s.toUTF8String(result);
-
-    return result;
+    ++i;
+    return *this;
   }
 
-  inline
-  bool
-  empty(const String& s)
+  UnicodeStringIterator
+  operator+(int32_t v)
   {
-    return s.isEmpty();
+    return UnicodeStringIterator(s, i + v);
   }
+
+  private:
+  const icu::UnicodeString* s;
+  int32_t i;
+};
+#if defined(__GNUC__)
+#pragma GCC diagnostic pop
+#endif
+
+inline
+String&
+stringAppend(String&s, String a)
+{
+  return s.append(std::move(a));
 }
 
-namespace std
+inline
+String&
+stringAppend(String& s, size_t n, UChar32 c)
 {
-  inline
-  cxxopts::UnicodeStringIterator
-  begin(const icu::UnicodeString& s)
+  for (size_t i = 0; i != n; ++i)
   {
-    return cxxopts::UnicodeStringIterator(&s, 0);
+    s.append(c);
   }
 
-  inline
-  cxxopts::UnicodeStringIterator
-  end(const icu::UnicodeString& s)
+  return s;
+}
+
+template <typename Iterator>
+String&
+stringAppend(String& s, Iterator begin, Iterator end)
+{
+  while (begin != end)
   {
-    return cxxopts::UnicodeStringIterator(&s, s.length());
+    s.append(*begin);
+    ++begin;
   }
+
+  return s;
 }
 
+inline
+size_t
+stringLength(const String& s)
+{
+  return s.length();
+}
+
+inline
+std::string
+toUTF8String(const String& s)
+{
+  std::string result;
+  s.toUTF8String(result);
+
+  return result;
+}
+
+inline
+bool
+empty(const String& s)
+{
+  return s.isEmpty();
+}
+
+} // namespace cxxopts
+
+namespace std {
+inline
+cxxopts::UnicodeStringIterator
+begin(const icu::UnicodeString& s)
+{
+  return cxxopts::UnicodeStringIterator(&s, 0);
+}
+
+inline
+cxxopts::UnicodeStringIterator
+end(const icu::UnicodeString& s)
+{
+  return cxxopts::UnicodeStringIterator(&s, s.length());
+}
+
+} // namespace std
+
 //ifdef CXXOPTS_USE_UNICODE
 #else
 
-namespace cxxopts
+namespace cxxopts {
+using String = std::string;
+
+template <typename T>
+T
+toLocalString(T&& t)
 {
-  using String = std::string;
+  return std::forward<T>(t);
+}
 
-  template <typename T>
-  T
-  toLocalString(T&& t)
-  {
-    return std::forward<T>(t);
-  }
+inline
+size_t
+stringLength(const String& s)
+{
+  return s.length();
+}
 
-  inline
-  size_t
-  stringLength(const String& s)
-  {
-    return s.length();
-  }
+inline
+String&
+stringAppend(String&s, const String& a)
+{
+  return s.append(a);
+}
 
-  inline
-  String&
-  stringAppend(String&s, const String& a)
-  {
-    return s.append(a);
-  }
+inline
+String&
+stringAppend(String& s, size_t n, char c)
+{
+  return s.append(n, c);
+}
 
-  inline
-  String&
-  stringAppend(String& s, size_t n, char c)
-  {
-    return s.append(n, c);
-  }
+template <typename Iterator>
+String&
+stringAppend(String& s, Iterator begin, Iterator end)
+{
+  return s.append(begin, end);
+}
 
-  template <typename Iterator>
-  String&
-  stringAppend(String& s, Iterator begin, Iterator end)
-  {
-    return s.append(begin, end);
-  }
+template <typename T>
+std::string
+toUTF8String(T&& t)
+{
+  return std::forward<T>(t);
+}
 
-  template <typename T>
-  std::string
-  toUTF8String(T&& t)
-  {
-    return std::forward<T>(t);
-  }
+inline
+bool
+empty(const std::string& s)
+{
+  return s.empty();
+}
 
-  inline
-  bool
-  empty(const std::string& s)
-  {
-    return s.empty();
-  }
 } // namespace cxxopts
 
 //ifdef CXXOPTS_USE_UNICODE
 #endif
 
-namespace cxxopts
-{
-  namespace
-  {
+namespace cxxopts {
+namespace {
 #ifdef _WIN32
-    const std::string LQUOTE("\'");
-    const std::string RQUOTE("\'");
+const std::string LQUOTE("\'");
+const std::string RQUOTE("\'");
 #else
-    const std::string LQUOTE("‘");
-    const std::string RQUOTE("’");
+const std::string LQUOTE("‘");
+const std::string RQUOTE("’");
 #endif
-  } // namespace
+} // namespace
 
 #if defined(__GNUC__)
 // GNU GCC with -Weffc++ will issue a warning regarding the upcoming class, we want to silence it:
@@ -323,1764 +320,1761 @@ namespace cxxopts
 #pragma GCC diagnostic ignored "-Weffc++"
 // This will be ignored under other compilers like LLVM clang.
 #endif
-  class Value : public std::enable_shared_from_this<Value>
-  {
-    public:
+class Value : public std::enable_shared_from_this<Value>
+{
+  public:
 
-    virtual ~Value() = default;
+  virtual ~Value() = default;
 
-    virtual
-    std::shared_ptr<Value>
-    clone() const = 0;
+  virtual
+  std::shared_ptr<Value>
+  clone() const = 0;
 
-    virtual void
-    parse(const std::string& text) const = 0;
+  virtual void
+  parse(const std::string& text) const = 0;
 
-    virtual void
-    parse() const = 0;
+  virtual void
+  parse() const = 0;
 
-    virtual bool
-    has_default() const = 0;
+  virtual bool
+  has_default() const = 0;
 
-    virtual bool
-    is_container() const = 0;
+  virtual bool
+  is_container() const = 0;
 
-    virtual bool
-    has_implicit() const = 0;
+  virtual bool
+  has_implicit() const = 0;
 
-    virtual std::string
-    get_default_value() const = 0;
+  virtual std::string
+  get_default_value() const = 0;
 
-    virtual std::string
-    get_implicit_value() const = 0;
+  virtual std::string
+  get_implicit_value() const = 0;
 
-    virtual std::shared_ptr<Value>
-    default_value(const std::string& value) = 0;
+  virtual std::shared_ptr<Value>
+  default_value(const std::string& value) = 0;
 
-    virtual std::shared_ptr<Value>
-    implicit_value(const std::string& value) = 0;
+  virtual std::shared_ptr<Value>
+  implicit_value(const std::string& value) = 0;
 
-    virtual std::shared_ptr<Value>
-    no_implicit_value() = 0;
+  virtual std::shared_ptr<Value>
+  no_implicit_value() = 0;
 
-    virtual bool
-    is_boolean() const = 0;
-  };
+  virtual bool
+  is_boolean() const = 0;
+};
 #if defined(__GNUC__)
 #pragma GCC diagnostic pop
 #endif
-  class OptionException : public std::exception
+class OptionException : public std::exception
+{
+  public:
+  explicit OptionException(std::string  message)
+  : m_message(std::move(message))
   {
-    public:
-    explicit OptionException(std::string  message)
-    : m_message(std::move(message))
-    {
-    }
+  }
 
-    CXXOPTS_NODISCARD
-    const char*
-    what() const noexcept override
-    {
-      return m_message.c_str();
-    }
+  CXXOPTS_NODISCARD
+  const char*
+  what() const noexcept override
+  {
+    return m_message.c_str();
+  }
 
-    private:
-    std::string m_message;
-  };
+  private:
+  std::string m_message;
+};
+
+class OptionSpecException : public OptionException
+{
+  public:
 
-  class OptionSpecException : public OptionException
+  explicit OptionSpecException(const std::string& message)
+  : OptionException(message)
   {
-    public:
+  }
+};
 
-    explicit OptionSpecException(const std::string& message)
-    : OptionException(message)
-    {
-    }
-  };
+class OptionParseException : public OptionException
+{
+  public:
+  explicit OptionParseException(const std::string& message)
+  : OptionException(message)
+  {
+  }
+};
 
-  class OptionParseException : public OptionException
+class option_exists_error : public OptionSpecException
+{
+  public:
+  explicit option_exists_error(const std::string& option)
+  : OptionSpecException("Option " + LQUOTE + option + RQUOTE + " already exists")
   {
-    public:
-    explicit OptionParseException(const std::string& message)
-    : OptionException(message)
-    {
-    }
-  };
+  }
+};
 
-  class option_exists_error : public OptionSpecException
+class invalid_option_format_error : public OptionSpecException
+{
+  public:
+  explicit invalid_option_format_error(const std::string& format)
+  : OptionSpecException("Invalid option format " + LQUOTE + format + RQUOTE)
   {
-    public:
-    explicit option_exists_error(const std::string& option)
-    : OptionSpecException("Option " + LQUOTE + option + RQUOTE + " already exists")
-    {
-    }
-  };
+  }
+};
 
-  class invalid_option_format_error : public OptionSpecException
+class option_syntax_exception : public OptionParseException {
+  public:
+  explicit option_syntax_exception(const std::string& text)
+  : OptionParseException("Argument " + LQUOTE + text + RQUOTE +
+      " starts with a - but has incorrect syntax")
   {
-    public:
-    explicit invalid_option_format_error(const std::string& format)
-    : OptionSpecException("Invalid option format " + LQUOTE + format + RQUOTE)
-    {
-    }
-  };
+  }
+};
 
-  class option_syntax_exception : public OptionParseException {
-    public:
-    explicit option_syntax_exception(const std::string& text)
-    : OptionParseException("Argument " + LQUOTE + text + RQUOTE +
-        " starts with a - but has incorrect syntax")
-    {
-    }
-  };
+class option_not_exists_exception : public OptionParseException
+{
+  public:
+  explicit option_not_exists_exception(const std::string& option)
+  : OptionParseException("Option " + LQUOTE + option + RQUOTE + " does not exist")
+  {
+  }
+};
 
-  class option_not_exists_exception : public OptionParseException
+class missing_argument_exception : public OptionParseException
+{
+  public:
+  explicit missing_argument_exception(const std::string& option)
+  : OptionParseException(
+      "Option " + LQUOTE + option + RQUOTE + " is missing an argument"
+    )
   {
-    public:
-    explicit option_not_exists_exception(const std::string& option)
-    : OptionParseException("Option " + LQUOTE + option + RQUOTE + " does not exist")
-    {
-    }
-  };
+  }
+};
 
-  class missing_argument_exception : public OptionParseException
+class option_requires_argument_exception : public OptionParseException
+{
+  public:
+  explicit option_requires_argument_exception(const std::string& option)
+  : OptionParseException(
+      "Option " + LQUOTE + option + RQUOTE + " requires an argument"
+    )
   {
-    public:
-    explicit missing_argument_exception(const std::string& option)
-    : OptionParseException(
-        "Option " + LQUOTE + option + RQUOTE + " is missing an argument"
-      )
-    {
-    }
-  };
+  }
+};
 
-  class option_requires_argument_exception : public OptionParseException
+class option_not_has_argument_exception : public OptionParseException
+{
+  public:
+  option_not_has_argument_exception
+  (
+    const std::string& option,
+    const std::string& arg
+  )
+  : OptionParseException(
+      "Option " + LQUOTE + option + RQUOTE +
+      " does not take an argument, but argument " +
+      LQUOTE + arg + RQUOTE + " given"
+    )
   {
-    public:
-    explicit option_requires_argument_exception(const std::string& option)
-    : OptionParseException(
-        "Option " + LQUOTE + option + RQUOTE + " requires an argument"
-      )
-    {
-    }
-  };
+  }
+};
 
-  class option_not_has_argument_exception : public OptionParseException
+class option_not_present_exception : public OptionParseException
+{
+  public:
+  explicit option_not_present_exception(const std::string& option)
+  : OptionParseException("Option " + LQUOTE + option + RQUOTE + " not present")
   {
-    public:
-    option_not_has_argument_exception
-    (
-      const std::string& option,
-      const std::string& arg
+  }
+};
+
+class option_has_no_value_exception : public OptionException
+{
+  public:
+  explicit option_has_no_value_exception(const std::string& option)
+  : OptionException(
+      !option.empty() ?
+      ("Option " + LQUOTE + option + RQUOTE + " has no value") :
+      "Option has no value")
+  {
+  }
+};
+
+class argument_incorrect_type : public OptionParseException
+{
+  public:
+  explicit argument_incorrect_type
+  (
+    const std::string& arg
+  )
+  : OptionParseException(
+      "Argument " + LQUOTE + arg + RQUOTE + " failed to parse"
     )
-    : OptionParseException(
-        "Option " + LQUOTE + option + RQUOTE +
-        " does not take an argument, but argument " +
-        LQUOTE + arg + RQUOTE + " given"
-      )
-    {
-    }
-  };
+  {
+  }
+};
 
-  class option_not_present_exception : public OptionParseException
+class option_required_exception : public OptionParseException
+{
+  public:
+  explicit option_required_exception(const std::string& option)
+  : OptionParseException(
+      "Option " + LQUOTE + option + RQUOTE + " is required but not present"
+    )
   {
-    public:
-    explicit option_not_present_exception(const std::string& option)
-    : OptionParseException("Option " + LQUOTE + option + RQUOTE + " not present")
-    {
-    }
-  };
+  }
+};
 
-  class option_has_no_value_exception : public OptionException
+template <typename T>
+void throw_or_mimic(const std::string& text)
+{
+  static_assert(std::is_base_of<std::exception, T>::value,
+                "throw_or_mimic only works on std::exception and "
+                "deriving classes");
+
+#ifndef CXXOPTS_NO_EXCEPTIONS
+  // If CXXOPTS_NO_EXCEPTIONS is not defined, just throw
+  throw T{text};
+#else
+  // Otherwise manually instantiate the exception, print what() to stderr,
+  // and exit
+  T exception{text};
+  std::cerr << exception.what() << std::endl;
+  std::exit(EXIT_FAILURE);
+#endif
+}
+
+namespace values {
+namespace parser_tool {
+struct IntegerDesc
+{
+  std::string negative = "";
+  std::string base     = "";
+  std::string value    = "";
+};
+struct ArguDesc {
+  std::string arg_name  = "";
+  bool        grouping  = false;
+  bool        set_value = false;
+  std::string value     = "";
+};
+#ifdef CXXOPTS_NO_REGEX
+inline IntegerDesc SplitInteger(const std::string &text)
+{
+  if (text.empty())
   {
-    public:
-    explicit option_has_no_value_exception(const std::string& option)
-    : OptionException(
-        !option.empty() ?
-        ("Option " + LQUOTE + option + RQUOTE + " has no value") :
-        "Option has no value")
-    {
-    }
-  };
+    throw_or_mimic<argument_incorrect_type>(text);
+  }
+  IntegerDesc desc;
+  const char *pdata = text.c_str();
+  if (*pdata == '-')
+  {
+    pdata += 1;
+    desc.negative = "-";
+  }
+  if (strncmp(pdata, "0x", 2) == 0)
+  {
+    pdata += 2;
+    desc.base = "0x";
+  }
+  if (*pdata != '\0')
+  {
+    desc.value = std::string(pdata);
+  }
+  else
+  {
+    throw_or_mimic<argument_incorrect_type>(text);
+  }
+  return desc;
+}
 
-  class argument_incorrect_type : public OptionParseException
+inline bool IsTrueText(const std::string &text)
+{
+  const char *pdata = text.c_str();
+  if (*pdata == 't' || *pdata == 'T')
   {
-    public:
-    explicit argument_incorrect_type
-    (
-      const std::string& arg
-    )
-    : OptionParseException(
-        "Argument " + LQUOTE + arg + RQUOTE + " failed to parse"
-      )
+    pdata += 1;
+    if (strncmp(pdata, "rue\0", 4) == 0)
     {
+      return true;
     }
-  };
+  }
+  else if (strncmp(pdata, "1\0", 2) == 0)
+  {
+    return true;
+  }
+  return false;
+}
 
-  class option_required_exception : public OptionParseException
+inline bool IsFalseText(const std::string &text)
+{
+  const char *pdata = text.c_str();
+  if (*pdata == 'f' || *pdata == 'F')
   {
-    public:
-    explicit option_required_exception(const std::string& option)
-    : OptionParseException(
-        "Option " + LQUOTE + option + RQUOTE + " is required but not present"
-      )
+    pdata += 1;
+    if (strncmp(pdata, "alse\0", 5) == 0)
     {
+      return true;
     }
-  };
-
-  template <typename T>
-  void throw_or_mimic(const std::string& text)
+  }
+  else if (strncmp(pdata, "0\0", 2) == 0)
   {
-    static_assert(std::is_base_of<std::exception, T>::value,
-                  "throw_or_mimic only works on std::exception and "
-                  "deriving classes");
+    return true;
+  }
+  return false;
+}
 
-#ifndef CXXOPTS_NO_EXCEPTIONS
-    // If CXXOPTS_NO_EXCEPTIONS is not defined, just throw
-    throw T{text};
-#else
-    // Otherwise manually instantiate the exception, print what() to stderr,
-    // and exit
-    T exception{text};
-    std::cerr << exception.what() << std::endl;
-    std::exit(EXIT_FAILURE);
-#endif
+inline std::pair<std::string, std::string> SplitSwitchDef(const std::string &text)
+{
+  std::string short_sw, long_sw;
+  const char *pdata = text.c_str();
+  if (isalnum(*pdata) && *(pdata + 1) == ',') {
+    short_sw = std::string(1, *pdata);
+    pdata += 2;
+  }
+  while (*pdata == ' ') { pdata += 1; }
+  if (isalnum(*pdata)) {
+    const char *store = pdata;
+    pdata += 1;
+    while (isalnum(*pdata) || *pdata == '-' || *pdata == '_') {
+      pdata += 1;
+    }
+    if (*pdata == '\0') {
+      long_sw = std::string(store, pdata - store);
+    } else {
+      throw_or_mimic<invalid_option_format_error>(text);
+    }
   }
+  return std::pair<std::string, std::string>(short_sw, long_sw);
+}
 
-  namespace values
+inline ArguDesc ParseArgument(const char *arg, bool &matched)
+{
+  ArguDesc argu_desc;
+  const char *pdata = arg;
+  matched = false;
+  if (strncmp(pdata, "--", 2) == 0)
   {
-    namespace parser_tool
+    pdata += 2;
+    if (isalnum(*pdata))
     {
-      struct IntegerDesc
+      argu_desc.arg_name.push_back(*pdata);
+      pdata += 1;
+      while (isalnum(*pdata) || *pdata == '-' || *pdata == '_')
       {
-        std::string negative = "";
-        std::string base     = "";
-        std::string value    = "";
-      };
-      struct ArguDesc {
-        std::string arg_name  = "";
-        bool        grouping  = false;
-        bool        set_value = false;
-        std::string value     = "";
-      };
-#ifdef CXXOPTS_NO_REGEX
-      inline IntegerDesc SplitInteger(const std::string &text)
-      {
-        if (text.empty())
-        {
-          throw_or_mimic<argument_incorrect_type>(text);
-        }
-        IntegerDesc desc;
-        const char *pdata = text.c_str();
-        if (*pdata == '-')
-        {
-          pdata += 1;
-          desc.negative = "-";
-        }
-        if (strncmp(pdata, "0x", 2) == 0)
-        {
-          pdata += 2;
-          desc.base = "0x";
-        }
-        if (*pdata != '\0')
-        {
-          desc.value = std::string(pdata);
-        }
-        else
-        {
-          throw_or_mimic<argument_incorrect_type>(text);
-        }
-        return desc;
+        argu_desc.arg_name.push_back(*pdata);
+        pdata += 1;
       }
-
-      inline bool IsTrueText(const std::string &text)
+      if (argu_desc.arg_name.length() > 1)
       {
-        const char *pdata = text.c_str();
-        if (*pdata == 't' || *pdata == 'T')
+        if (*pdata == '=')
         {
+          argu_desc.set_value = true;
           pdata += 1;
-          if (strncmp(pdata, "rue\0", 4) == 0)
+          if (*pdata != '\0')
           {
-            return true;
+            argu_desc.value = std::string(pdata);
           }
+          matched = true;
         }
-        else if (strncmp(pdata, "1\0", 2) == 0)
+        else if (*pdata == '\0')
         {
-          return true;
+          matched = true;
         }
-        return false;
-      }
-
-      inline bool IsFalseText(const std::string &text)
-      {
-        const char *pdata = text.c_str();
-        if (*pdata == 'f' || *pdata == 'F')
-        {
-          pdata += 1;
-          if (strncmp(pdata, "alse\0", 5) == 0)
-          {
-            return true;
-          }
-        }
-        else if (strncmp(pdata, "0\0", 2) == 0)
-        {
-          return true;
-        }
-        return false;
       }
+    }
+  }
+  else if (strncmp(pdata, "-", 1) == 0)
+  {
+    pdata += 1;
+    argu_desc.grouping = true;
+    while (isalnum(*pdata))
+    {
+      argu_desc.arg_name.push_back(*pdata);
+      pdata += 1;
+    }
+    matched = !argu_desc.arg_name.empty() && *pdata == '\0';
+  }
+  return argu_desc;
+}
 
-      inline std::pair<std::string, std::string> SplitSwitchDef(const std::string &text)
-      {
-        std::string short_sw, long_sw;
-        const char *pdata = text.c_str();
-        if (isalnum(*pdata) && *(pdata + 1) == ',') {
-          short_sw = std::string(1, *pdata);
-          pdata += 2;
-        }
-        while (*pdata == ' ') { pdata += 1; }
-        if (isalnum(*pdata)) {
-          const char *store = pdata;
-          pdata += 1;
-          while (isalnum(*pdata) || *pdata == '-' || *pdata == '_') {
-            pdata += 1;
-          }
-          if (*pdata == '\0') {
-            long_sw = std::string(store, pdata - store);
-          } else {
-            throw_or_mimic<invalid_option_format_error>(text);
-          }
-        }
-        return std::pair<std::string, std::string>(short_sw, long_sw);
-      }
+#else  // CXXOPTS_NO_REGEX
 
-      inline ArguDesc ParseArgument(const char *arg, bool &matched)
-      {
-        ArguDesc argu_desc;
-        const char *pdata = arg;
-        matched = false;
-        if (strncmp(pdata, "--", 2) == 0)
-        {
-          pdata += 2;
-          if (isalnum(*pdata))
-          {
-            argu_desc.arg_name.push_back(*pdata);
-            pdata += 1;
-            while (isalnum(*pdata) || *pdata == '-' || *pdata == '_')
-            {
-              argu_desc.arg_name.push_back(*pdata);
-              pdata += 1;
-            }
-            if (argu_desc.arg_name.length() > 1)
-            {
-              if (*pdata == '=')
-              {
-                argu_desc.set_value = true;
-                pdata += 1;
-                if (*pdata != '\0')
-                {
-                  argu_desc.value = std::string(pdata);
-                }
-                matched = true;
-              }
-              else if (*pdata == '\0')
-              {
-                matched = true;
-              }
-            }
-          }
-        }
-        else if (strncmp(pdata, "-", 1) == 0)
-        {
-          pdata += 1;
-          argu_desc.grouping = true;
-          while (isalnum(*pdata))
-          {
-            argu_desc.arg_name.push_back(*pdata);
-            pdata += 1;
-          }
-          matched = !argu_desc.arg_name.empty() && *pdata == '\0';
-        }
-        return argu_desc;
-      }
+namespace {
 
-#else  // CXXOPTS_NO_REGEX
+std::basic_regex<char> integer_pattern
+  ("(-)?(0x)?([0-9a-zA-Z]+)|((0x)?0)");
+std::basic_regex<char> truthy_pattern
+  ("(t|T)(rue)?|1");
+std::basic_regex<char> falsy_pattern
+  ("(f|F)(alse)?|0");
 
-      namespace
-      {
+std::basic_regex<char> option_matcher
+  ("--([[:alnum:]][-_[:alnum:]]+)(=(.*))?|-([[:alnum:]]+)");
+std::basic_regex<char> option_specifier
+  ("(([[:alnum:]]),)?[ ]*([[:alnum:]][-_[:alnum:]]*)?");
 
-        std::basic_regex<char> integer_pattern
-          ("(-)?(0x)?([0-9a-zA-Z]+)|((0x)?0)");
-        std::basic_regex<char> truthy_pattern
-          ("(t|T)(rue)?|1");
-        std::basic_regex<char> falsy_pattern
-          ("(f|F)(alse)?|0");
+} // namespace
 
-        std::basic_regex<char> option_matcher
-          ("--([[:alnum:]][-_[:alnum:]]+)(=(.*))?|-([[:alnum:]]+)");
-        std::basic_regex<char> option_specifier
-          ("(([[:alnum:]]),)?[ ]*([[:alnum:]][-_[:alnum:]]*)?");
+inline IntegerDesc SplitInteger(const std::string &text)
+{
+  std::smatch match;
+  std::regex_match(text, match, integer_pattern);
 
-      } // namespace
+  if (match.length() == 0)
+  {
+    throw_or_mimic<argument_incorrect_type>(text);
+  }
 
-      inline IntegerDesc SplitInteger(const std::string &text)
-      {
-        std::smatch match;
-        std::regex_match(text, match, integer_pattern);
+  IntegerDesc desc;
+  desc.negative = match[1];
+  desc.base = match[2];
+  desc.value = match[3];
 
-        if (match.length() == 0)
-        {
-          throw_or_mimic<argument_incorrect_type>(text);
-        }
+  if (match.length(4) > 0)
+  {
+    desc.base = match[5];
+    desc.value = "0";
+    return desc;
+  }
 
-        IntegerDesc desc;
-        desc.negative = match[1];
-        desc.base = match[2];
-        desc.value = match[3];
+  return desc;
 
-        if (match.length(4) > 0)
-        {
-          desc.base = match[5];
-          desc.value = "0";
-          return desc;
-        }
+}
 
-        return desc;
-      }
+inline bool IsTrueText(const std::string &text)
+{
+  std::smatch result;
+  std::regex_match(text, result, truthy_pattern);
+  return !result.empty();
+}
 
-      inline bool IsTrueText(const std::string &text)
-      {
-        std::smatch result;
-        std::regex_match(text, result, truthy_pattern);
-        return !result.empty();
-      }
+inline bool IsFalseText(const std::string &text)
+{
+  std::smatch result;
+  std::regex_match(text, result, falsy_pattern);
+  return !result.empty();
+}
 
-      inline bool IsFalseText(const std::string &text)
-      {
-        std::smatch result;
-        std::regex_match(text, result, falsy_pattern);
-        return !result.empty();
-      }
+inline std::pair<std::string, std::string> SplitSwitchDef(const std::string &text)
+{
+  std::match_results<const char*> result;
+  std::regex_match(text.c_str(), result, option_specifier);
+  if (result.empty())
+  {
+    throw_or_mimic<invalid_option_format_error>(text);
+  }
 
-      inline std::pair<std::string, std::string> SplitSwitchDef(const std::string &text)
-      {
-        std::match_results<const char*> result;
-        std::regex_match(text.c_str(), result, option_specifier);
-        if (result.empty())
-        {
-          throw_or_mimic<invalid_option_format_error>(text);
-        }
+  const std::string& short_sw = result[2];
+  const std::string& long_sw = result[3];
 
-        const std::string& short_sw = result[2];
-        const std::string& long_sw = result[3];
+  return std::pair<std::string, std::string>(short_sw, long_sw);
+}
 
-        return std::pair<std::string, std::string>(short_sw, long_sw);
-      }
+inline ArguDesc ParseArgument(const char *arg, bool &matched)
+{
+  std::match_results<const char*> result;
+  std::regex_match(arg, result, option_matcher);
+  matched = !result.empty();
 
-      inline ArguDesc ParseArgument(const char *arg, bool &matched)
-      {
-        std::match_results<const char*> result;
-        std::regex_match(arg, result, option_matcher);
-        matched = !result.empty();
-
-        ArguDesc argu_desc;
-        if (matched) {
-          argu_desc.arg_name = result[1].str();
-          argu_desc.set_value = result[2].length() > 0;
-          argu_desc.value = result[3].str();
-          if (result[4].length() > 0)
-          {
-            argu_desc.grouping = true;
-            argu_desc.arg_name = result[4].str();
-          }
-        }
+  ArguDesc argu_desc;
+  if (matched) {
+    argu_desc.arg_name = result[1].str();
+    argu_desc.set_value = result[2].length() > 0;
+    argu_desc.value = result[3].str();
+    if (result[4].length() > 0)
+    {
+      argu_desc.grouping = true;
+      argu_desc.arg_name = result[4].str();
+    }
+  }
 
-        return argu_desc;
-      }
+  return argu_desc;
+}
 
 #endif  // CXXOPTS_NO_REGEX
 #undef CXXOPTS_NO_REGEX
-  }
-
-    namespace detail
-    {
-      template <typename T, bool B>
-      struct SignedCheck;
+} // namespace parser_tool
 
-      template <typename T>
-      struct SignedCheck<T, true>
-      {
-        template <typename U>
-        void
-        operator()(bool negative, U u, const std::string& text)
-        {
-          if (negative)
-          {
-            if (u > static_cast<U>((std::numeric_limits<T>::min)()))
-            {
-              throw_or_mimic<argument_incorrect_type>(text);
-            }
-          }
-          else
-          {
-            if (u > static_cast<U>((std::numeric_limits<T>::max)()))
-            {
-              throw_or_mimic<argument_incorrect_type>(text);
-            }
-          }
-        }
-      };
+namespace detail {
+template <typename T, bool B>
+struct SignedCheck;
 
-      template <typename T>
-      struct SignedCheck<T, false>
-      {
-        template <typename U>
-        void
-        operator()(bool, U, const std::string&) const {}
-      };
-
-      template <typename T, typename U>
-      void
-      check_signed_range(bool negative, U value, const std::string& text)
+template <typename T>
+struct SignedCheck<T, true>
+{
+  template <typename U>
+  void
+  operator()(bool negative, U u, const std::string& text)
+  {
+    if (negative)
+    {
+      if (u > static_cast<U>((std::numeric_limits<T>::min)()))
       {
-        SignedCheck<T, std::numeric_limits<T>::is_signed>()(negative, value, text);
+        throw_or_mimic<argument_incorrect_type>(text);
       }
-    } // namespace detail
-
-    template <typename R, typename T>
-    void
-    checked_negate(R& r, T&& t, const std::string&, std::true_type)
-    {
-      // if we got to here, then `t` is a positive number that fits into
-      // `R`. So to avoid MSVC C4146, we first cast it to `R`.
-      // See https://github.com/jarro2783/cxxopts/issues/62 for more details.
-      r = static_cast<R>(-static_cast<R>(t-1)-1);
     }
-
-    template <typename R, typename T>
-    void
-    checked_negate(R&, T&&, const std::string& text, std::false_type)
+    else
     {
-      throw_or_mimic<argument_incorrect_type>(text);
+      if (u > static_cast<U>((std::numeric_limits<T>::max)()))
+      {
+        throw_or_mimic<argument_incorrect_type>(text);
+      }
     }
+  }
+};
 
-    template <typename T>
-    void
-    integer_parser(const std::string& text, T& value)
-    {
-      parser_tool::IntegerDesc int_desc = parser_tool::SplitInteger(text);
+template <typename T>
+struct SignedCheck<T, false>
+{
+  template <typename U>
+  void
+  operator()(bool, U, const std::string&) const {}
+};
 
-      using US = typename std::make_unsigned<T>::type;
-      constexpr bool is_signed = std::numeric_limits<T>::is_signed;
+template <typename T, typename U>
+void
+check_signed_range(bool negative, U value, const std::string& text)
+{
+  SignedCheck<T, std::numeric_limits<T>::is_signed>()(negative, value, text);
+}
 
-      const bool          negative    = int_desc.negative.length() > 0;
-      const uint8_t       base        = int_desc.base.length() > 0 ? 16 : 10;
-      const std::string & value_match = int_desc.value;
+} // namespace detail
 
-      US result = 0;
+template <typename R, typename T>
+void
+checked_negate(R& r, T&& t, const std::string&, std::true_type)
+{
+  // if we got to here, then `t` is a positive number that fits into
+  // `R`. So to avoid MSVC C4146, we first cast it to `R`.
+  // See https://github.com/jarro2783/cxxopts/issues/62 for more details.
+  r = static_cast<R>(-static_cast<R>(t-1)-1);
+}
 
-      for (char ch : value_match)
-      {
-        US digit = 0;
+template <typename R, typename T>
+void
+checked_negate(R&, T&&, const std::string& text, std::false_type)
+{
+  throw_or_mimic<argument_incorrect_type>(text);
+}
 
-        if (ch >= '0' && ch <= '9')
-        {
-          digit = static_cast<US>(ch - '0');
-        }
-        else if (base == 16 && ch >= 'a' && ch <= 'f')
-        {
-          digit = static_cast<US>(ch - 'a' + 10);
-        }
-        else if (base == 16 && ch >= 'A' && ch <= 'F')
-        {
-          digit = static_cast<US>(ch - 'A' + 10);
-        }
-        else
-        {
-          throw_or_mimic<argument_incorrect_type>(text);
-        }
+template <typename T>
+void
+integer_parser(const std::string& text, T& value)
+{
+  parser_tool::IntegerDesc int_desc = parser_tool::SplitInteger(text);
 
-        const US next = static_cast<US>(result * base + digit);
-        if (result > next)
-        {
-          throw_or_mimic<argument_incorrect_type>(text);
-        }
+  using US = typename std::make_unsigned<T>::type;
+  constexpr bool is_signed = std::numeric_limits<T>::is_signed;
 
-        result = next;
-      }
+  const bool          negative    = int_desc.negative.length() > 0;
+  const uint8_t       base        = int_desc.base.length() > 0 ? 16 : 10;
+  const std::string & value_match = int_desc.value;
 
-      detail::check_signed_range<T>(negative, result, text);
+  US result = 0;
 
-      if (negative)
-      {
-        checked_negate<T>(value, result, text, std::integral_constant<bool, is_signed>());
-      }
-      else
-      {
-        value = static_cast<T>(result);
-      }
-    }
+  for (char ch : value_match)
+  {
+    US digit = 0;
 
-    template <typename T>
-    void stringstream_parser(const std::string& text, T& value)
+    if (ch >= '0' && ch <= '9')
     {
-      std::stringstream in(text);
-      in >> value;
-      if (!in) {
-        throw_or_mimic<argument_incorrect_type>(text);
-      }
+      digit = static_cast<US>(ch - '0');
     }
-
-    template <typename T,
-             typename std::enable_if<std::is_integral<T>::value>::type* = nullptr
-             >
-    void parse_value(const std::string& text, T& value)
+    else if (base == 16 && ch >= 'a' && ch <= 'f')
     {
-        integer_parser(text, value);
+      digit = static_cast<US>(ch - 'a' + 10);
     }
-
-    inline
-    void
-    parse_value(const std::string& text, bool& value)
+    else if (base == 16 && ch >= 'A' && ch <= 'F')
+    {
+      digit = static_cast<US>(ch - 'A' + 10);
+    }
+    else
     {
-      if (parser_tool::IsTrueText(text))
-      {
-        value = true;
-        return;
-      }
-
-      if (parser_tool::IsFalseText(text))
-      {
-        value = false;
-        return;
-      }
-
       throw_or_mimic<argument_incorrect_type>(text);
     }
 
-    inline
-    void
-    parse_value(const std::string& text, std::string& value)
+    const US next = static_cast<US>(result * base + digit);
+    if (result > next)
     {
-      value = text;
+      throw_or_mimic<argument_incorrect_type>(text);
     }
 
-    // The fallback parser. It uses the stringstream parser to parse all types
-    // that have not been overloaded explicitly.  It has to be placed in the
-    // source code before all other more specialized templates.
-    template <typename T,
-             typename std::enable_if<!std::is_integral<T>::value>::type* = nullptr
-             >
-    void
-    parse_value(const std::string& text, T& value) {
-      stringstream_parser(text, value);
-    }
+    result = next;
+  }
 
-    template <typename T>
-    void
-    parse_value(const std::string& text, std::vector<T>& value)
-    {
-      if (text.empty()) {
-        T v;
-        parse_value(text, v);
-        value.emplace_back(std::move(v));
-        return;
-      }
-      std::stringstream in(text);
-      std::string token;
-      while(!in.eof() && std::getline(in, token, CXXOPTS_VECTOR_DELIMITER)) {
-        T v;
-        parse_value(token, v);
-        value.emplace_back(std::move(v));
-      }
-    }
+  detail::check_signed_range<T>(negative, result, text);
 
-#ifdef CXXOPTS_HAS_OPTIONAL
-    template <typename T>
-    void
-    parse_value(const std::string& text, std::optional<T>& value)
-    {
-      T result;
-      parse_value(text, result);
-      value = std::move(result);
-    }
-#endif
+  if (negative)
+  {
+    checked_negate<T>(value, result, text, std::integral_constant<bool, is_signed>());
+  }
+  else
+  {
+    value = static_cast<T>(result);
+  }
+}
 
-    inline
-    void parse_value(const std::string& text, char& c)
-    {
-      if (text.length() != 1)
-      {
-        throw_or_mimic<argument_incorrect_type>(text);
-      }
+template <typename T>
+void stringstream_parser(const std::string& text, T& value)
+{
+  std::stringstream in(text);
+  in >> value;
+  if (!in) {
+    throw_or_mimic<argument_incorrect_type>(text);
+  }
+}
 
-      c = text[0];
-    }
+template <typename T,
+         typename std::enable_if<std::is_integral<T>::value>::type* = nullptr
+         >
+void parse_value(const std::string& text, T& value)
+{
+    integer_parser(text, value);
+}
 
-    template <typename T>
-    struct type_is_container
-    {
-      static constexpr bool value = false;
-    };
+inline
+void
+parse_value(const std::string& text, bool& value)
+{
+  if (parser_tool::IsTrueText(text))
+  {
+    value = true;
+    return;
+  }
 
-    template <typename T>
-    struct type_is_container<std::vector<T>>
-    {
-      static constexpr bool value = true;
-    };
+  if (parser_tool::IsFalseText(text))
+  {
+    value = false;
+    return;
+  }
 
-    template <typename T>
-    class abstract_value : public Value
-    {
-      using Self = abstract_value<T>;
+  throw_or_mimic<argument_incorrect_type>(text);
+}
 
-      public:
-      abstract_value()
-      : m_result(std::make_shared<T>())
-      , m_store(m_result.get())
-      {
-      }
+inline
+void
+parse_value(const std::string& text, std::string& value)
+{
+  value = text;
+}
 
-      explicit abstract_value(T* t)
-      : m_store(t)
-      {
-      }
+// The fallback parser. It uses the stringstream parser to parse all types
+// that have not been overloaded explicitly.  It has to be placed in the
+// source code before all other more specialized templates.
+template <typename T,
+         typename std::enable_if<!std::is_integral<T>::value>::type* = nullptr
+         >
+void
+parse_value(const std::string& text, T& value) {
+  stringstream_parser(text, value);
+}
 
-      ~abstract_value() override = default;
+template <typename T>
+void
+parse_value(const std::string& text, std::vector<T>& value)
+{
+  if (text.empty()) {
+    T v;
+    parse_value(text, v);
+    value.emplace_back(std::move(v));
+    return;
+  }
+  std::stringstream in(text);
+  std::string token;
+  while(!in.eof() && std::getline(in, token, CXXOPTS_VECTOR_DELIMITER)) {
+    T v;
+    parse_value(token, v);
+    value.emplace_back(std::move(v));
+  }
+}
 
-      abstract_value& operator=(const abstract_value&) = default;
+#ifdef CXXOPTS_HAS_OPTIONAL
+template <typename T>
+void
+parse_value(const std::string& text, std::optional<T>& value)
+{
+  T result;
+  parse_value(text, result);
+  value = std::move(result);
+}
+#endif
 
-      abstract_value(const abstract_value& rhs)
-      {
-        if (rhs.m_result)
-        {
-          m_result = std::make_shared<T>();
-          m_store = m_result.get();
-        }
-        else
-        {
-          m_store = rhs.m_store;
-        }
+inline
+void parse_value(const std::string& text, char& c)
+{
+  if (text.length() != 1)
+  {
+    throw_or_mimic<argument_incorrect_type>(text);
+  }
 
-        m_default = rhs.m_default;
-        m_implicit = rhs.m_implicit;
-        m_default_value = rhs.m_default_value;
-        m_implicit_value = rhs.m_implicit_value;
-      }
+  c = text[0];
+}
 
-      void
-      parse(const std::string& text) const override
-      {
-        parse_value(text, *m_store);
-      }
+template <typename T>
+struct type_is_container
+{
+  static constexpr bool value = false;
+};
 
-      bool
-      is_container() const override
-      {
-        return type_is_container<T>::value;
-      }
+template <typename T>
+struct type_is_container<std::vector<T>>
+{
+  static constexpr bool value = true;
+};
 
-      void
-      parse() const override
-      {
-        parse_value(m_default_value, *m_store);
-      }
+template <typename T>
+class abstract_value : public Value
+{
+  using Self = abstract_value<T>;
 
-      bool
-      has_default() const override
-      {
-        return m_default;
-      }
+  public:
+  abstract_value()
+  : m_result(std::make_shared<T>())
+  , m_store(m_result.get())
+  {
+  }
 
-      bool
-      has_implicit() const override
-      {
-        return m_implicit;
-      }
+  explicit abstract_value(T* t)
+  : m_store(t)
+  {
+  }
 
-      std::shared_ptr<Value>
-      default_value(const std::string& value) override
-      {
-        m_default = true;
-        m_default_value = value;
-        return shared_from_this();
-      }
+  ~abstract_value() override = default;
 
-      std::shared_ptr<Value>
-      implicit_value(const std::string& value) override
-      {
-        m_implicit = true;
-        m_implicit_value = value;
-        return shared_from_this();
-      }
+  abstract_value& operator=(const abstract_value&) = default;
 
-      std::shared_ptr<Value>
-      no_implicit_value() override
-      {
-        m_implicit = false;
-        return shared_from_this();
-      }
+  abstract_value(const abstract_value& rhs)
+  {
+    if (rhs.m_result)
+    {
+      m_result = std::make_shared<T>();
+      m_store = m_result.get();
+    }
+    else
+    {
+      m_store = rhs.m_store;
+    }
 
-      std::string
-      get_default_value() const override
-      {
-        return m_default_value;
-      }
+    m_default = rhs.m_default;
+    m_implicit = rhs.m_implicit;
+    m_default_value = rhs.m_default_value;
+    m_implicit_value = rhs.m_implicit_value;
+  }
 
-      std::string
-      get_implicit_value() const override
-      {
-        return m_implicit_value;
-      }
+  void
+  parse(const std::string& text) const override
+  {
+    parse_value(text, *m_store);
+  }
 
-      bool
-      is_boolean() const override
-      {
-        return std::is_same<T, bool>::value;
-      }
+  bool
+  is_container() const override
+  {
+    return type_is_container<T>::value;
+  }
 
-      const T&
-      get() const
-      {
-        if (m_store == nullptr)
-        {
-          return *m_result;
-        }
-        return *m_store;
-      }
+  void
+  parse() const override
+  {
+    parse_value(m_default_value, *m_store);
+  }
 
-      protected:
-      std::shared_ptr<T> m_result{};
-      T* m_store{};
+  bool
+  has_default() const override
+  {
+    return m_default;
+  }
 
-      bool m_default = false;
-      bool m_implicit = false;
+  bool
+  has_implicit() const override
+  {
+    return m_implicit;
+  }
 
-      std::string m_default_value{};
-      std::string m_implicit_value{};
-    };
+  std::shared_ptr<Value>
+  default_value(const std::string& value) override
+  {
+    m_default = true;
+    m_default_value = value;
+    return shared_from_this();
+  }
 
-    template <typename T>
-    class standard_value : public abstract_value<T>
-    {
-      public:
-      using abstract_value<T>::abstract_value;
+  std::shared_ptr<Value>
+  implicit_value(const std::string& value) override
+  {
+    m_implicit = true;
+    m_implicit_value = value;
+    return shared_from_this();
+  }
 
-      CXXOPTS_NODISCARD
-      std::shared_ptr<Value>
-      clone() const override
-      {
-        return std::make_shared<standard_value<T>>(*this);
-      }
-    };
+  std::shared_ptr<Value>
+  no_implicit_value() override
+  {
+    m_implicit = false;
+    return shared_from_this();
+  }
 
-    template <>
-    class standard_value<bool> : public abstract_value<bool>
-    {
-      public:
-      ~standard_value() override = default;
+  std::string
+  get_default_value() const override
+  {
+    return m_default_value;
+  }
 
-      standard_value()
-      {
-        set_default_and_implicit();
-      }
+  std::string
+  get_implicit_value() const override
+  {
+    return m_implicit_value;
+  }
 
-      explicit standard_value(bool* b)
-      : abstract_value(b)
-      {
-        set_default_and_implicit();
-      }
+  bool
+  is_boolean() const override
+  {
+    return std::is_same<T, bool>::value;
+  }
 
-      std::shared_ptr<Value>
-      clone() const override
-      {
-        return std::make_shared<standard_value<bool>>(*this);
-      }
+  const T&
+  get() const
+  {
+    if (m_store == nullptr)
+    {
+      return *m_result;
+    }
+    return *m_store;
+  }
 
-      private:
+  protected:
+  std::shared_ptr<T> m_result{};
+  T* m_store{};
 
-      void
-      set_default_and_implicit()
-      {
-        m_default = true;
-        m_default_value = "false";
-        m_implicit = true;
-        m_implicit_value = "true";
-      }
-    };
-  } // namespace values
+  bool m_default = false;
+  bool m_implicit = false;
 
-  template <typename T>
+  std::string m_default_value{};
+  std::string m_implicit_value{};
+};
+
+template <typename T>
+class standard_value : public abstract_value<T>
+{
+  public:
+  using abstract_value<T>::abstract_value;
+
+  CXXOPTS_NODISCARD
   std::shared_ptr<Value>
-  value()
+  clone() const override
   {
-    return std::make_shared<values::standard_value<T>>();
+    return std::make_shared<standard_value<T>>(*this);
+  }
+};
+
+template <>
+class standard_value<bool> : public abstract_value<bool>
+{
+  public:
+  ~standard_value() override = default;
+
+  standard_value()
+  {
+    set_default_and_implicit();
+  }
+
+  explicit standard_value(bool* b)
+  : abstract_value(b)
+  {
+    set_default_and_implicit();
   }
 
-  template <typename T>
   std::shared_ptr<Value>
-  value(T& t)
+  clone() const override
   {
-    return std::make_shared<values::standard_value<T>>(&t);
+    return std::make_shared<standard_value<bool>>(*this);
   }
 
-  class OptionAdder;
+  private:
 
-  class OptionDetails
+  void
+  set_default_and_implicit()
   {
-    public:
-    OptionDetails
-    (
-      std::string short_,
-      std::string long_,
-      String desc,
-      std::shared_ptr<const Value> val
-    )
-    : m_short(std::move(short_))
-    , m_long(std::move(long_))
-    , m_desc(std::move(desc))
-    , m_value(std::move(val))
-    , m_count(0)
-    {
-      m_hash = std::hash<std::string>{}(m_long + m_short);
-    }
+    m_default = true;
+    m_default_value = "false";
+    m_implicit = true;
+    m_implicit_value = "true";
+  }
+};
+} // namespace values
 
-    OptionDetails(const OptionDetails& rhs)
-    : m_desc(rhs.m_desc)
-    , m_value(rhs.m_value->clone())
-    , m_count(rhs.m_count)
-    {
-    }
+template <typename T>
+std::shared_ptr<Value>
+value()
+{
+  return std::make_shared<values::standard_value<T>>();
+}
 
-    OptionDetails(OptionDetails&& rhs) = default;
+template <typename T>
+std::shared_ptr<Value>
+value(T& t)
+{
+  return std::make_shared<values::standard_value<T>>(&t);
+}
 
-    CXXOPTS_NODISCARD
-    const String&
-    description() const
-    {
-      return m_desc;
-    }
+class OptionAdder;
 
-    CXXOPTS_NODISCARD
-    const Value&
-    value() const {
-        return *m_value;
-    }
+class OptionDetails
+{
+  public:
+  OptionDetails
+  (
+    std::string short_,
+    std::string long_,
+    String desc,
+    std::shared_ptr<const Value> val
+  )
+  : m_short(std::move(short_))
+  , m_long(std::move(long_))
+  , m_desc(std::move(desc))
+  , m_value(std::move(val))
+  , m_count(0)
+  {
+    m_hash = std::hash<std::string>{}(m_long + m_short);
+  }
 
-    CXXOPTS_NODISCARD
-    std::shared_ptr<Value>
-    make_storage() const
-    {
-      return m_value->clone();
-    }
+  OptionDetails(const OptionDetails& rhs)
+  : m_desc(rhs.m_desc)
+  , m_value(rhs.m_value->clone())
+  , m_count(rhs.m_count)
+  {
+  }
 
-    CXXOPTS_NODISCARD
-    const std::string&
-    short_name() const
-    {
-      return m_short;
-    }
+  OptionDetails(OptionDetails&& rhs) = default;
 
-    CXXOPTS_NODISCARD
-    const std::string&
-    long_name() const
-    {
-      return m_long;
-    }
+  CXXOPTS_NODISCARD
+  const String&
+  description() const
+  {
+    return m_desc;
+  }
 
-    CXXOPTS_NODISCARD
-    const std::string&
-    essential_name() const
-    {
-      return m_long.empty() ? m_short : m_long;
-    }
+  CXXOPTS_NODISCARD
+  const Value&
+  value() const {
+      return *m_value;
+  }
 
-    size_t
-    hash() const
-    {
-      return m_hash;
-    }
+  CXXOPTS_NODISCARD
+  std::shared_ptr<Value>
+  make_storage() const
+  {
+    return m_value->clone();
+  }
 
-    private:
-    std::string m_short{};
-    std::string m_long{};
-    String m_desc{};
-    std::shared_ptr<const Value> m_value{};
-    int m_count;
+  CXXOPTS_NODISCARD
+  const std::string&
+  short_name() const
+  {
+    return m_short;
+  }
 
-    size_t m_hash{};
-  };
+  CXXOPTS_NODISCARD
+  const std::string&
+  long_name() const
+  {
+    return m_long;
+  }
 
-  struct HelpOptionDetails
-  {
-    std::string s;
-    std::string l;
-    String desc;
-    bool has_default;
-    std::string default_value;
-    bool has_implicit;
-    std::string implicit_value;
-    std::string arg_help;
-    bool is_container;
-    bool is_boolean;
-  };
+  CXXOPTS_NODISCARD
+  const std::string&
+  essential_name() const
+  {
+    return m_long.empty() ? m_short : m_long;
+  }
 
-  struct HelpGroupDetails
+  size_t
+  hash() const
   {
-    std::string name{};
-    std::string description{};
-    std::vector<HelpOptionDetails> options{};
-  };
+    return m_hash;
+  }
 
-  class OptionValue
+  private:
+  std::string m_short{};
+  std::string m_long{};
+  String m_desc{};
+  std::shared_ptr<const Value> m_value{};
+  int m_count;
+
+  size_t m_hash{};
+};
+
+struct HelpOptionDetails
+{
+  std::string s;
+  std::string l;
+  String desc;
+  bool has_default;
+  std::string default_value;
+  bool has_implicit;
+  std::string implicit_value;
+  std::string arg_help;
+  bool is_container;
+  bool is_boolean;
+};
+
+struct HelpGroupDetails
+{
+  std::string name{};
+  std::string description{};
+  std::vector<HelpOptionDetails> options{};
+};
+
+class OptionValue
+{
+  public:
+  void
+  parse
+  (
+    const std::shared_ptr<const OptionDetails>& details,
+    const std::string& text
+  )
   {
-    public:
-    void
-    parse
-    (
-      const std::shared_ptr<const OptionDetails>& details,
-      const std::string& text
-    )
-    {
-      ensure_value(details);
-      ++m_count;
-      m_value->parse(text);
-      m_long_name = &details->long_name();
-    }
+    ensure_value(details);
+    ++m_count;
+    m_value->parse(text);
+    m_long_name = &details->long_name();
+  }
 
-    void
-    parse_default(const std::shared_ptr<const OptionDetails>& details)
-    {
-      ensure_value(details);
-      m_default = true;
-      m_long_name = &details->long_name();
-      m_value->parse();
-    }
+  void
+  parse_default(const std::shared_ptr<const OptionDetails>& details)
+  {
+    ensure_value(details);
+    m_default = true;
+    m_long_name = &details->long_name();
+    m_value->parse();
+  }
 
-    void
-    parse_no_value(const std::shared_ptr<const OptionDetails>& details)
-    {
-      m_long_name = &details->long_name();
-    }
+  void
+  parse_no_value(const std::shared_ptr<const OptionDetails>& details)
+  {
+    m_long_name = &details->long_name();
+  }
 
 #if defined(CXXOPTS_NULL_DEREF_IGNORE)
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wnull-dereference"
 #endif
 
-    CXXOPTS_NODISCARD
-    size_t
-    count() const noexcept
-    {
-      return m_count;
-    }
+  CXXOPTS_NODISCARD
+  size_t
+  count() const noexcept
+  {
+    return m_count;
+  }
 
 #if defined(CXXOPTS_NULL_DEREF_IGNORE)
 #pragma GCC diagnostic pop
 #endif
 
-    // TODO: maybe default options should count towards the number of arguments
-    CXXOPTS_NODISCARD
-    bool
-    has_default() const noexcept
-    {
-      return m_default;
-    }
+  // TODO: maybe default options should count towards the number of arguments
+  CXXOPTS_NODISCARD
+  bool
+  has_default() const noexcept
+  {
+    return m_default;
+  }
 
-    template <typename T>
-    const T&
-    as() const
-    {
-      if (m_value == nullptr) {
-          throw_or_mimic<option_has_no_value_exception>(
-              m_long_name == nullptr ? "" : *m_long_name);
-      }
+  template <typename T>
+  const T&
+  as() const
+  {
+    if (m_value == nullptr) {
+        throw_or_mimic<option_has_no_value_exception>(
+            m_long_name == nullptr ? "" : *m_long_name);
+    }
 
 #ifdef CXXOPTS_NO_RTTI
-      return static_cast<const values::standard_value<T>&>(*m_value).get();
+    return static_cast<const values::standard_value<T>&>(*m_value).get();
 #else
-      return dynamic_cast<const values::standard_value<T>&>(*m_value).get();
+    return dynamic_cast<const values::standard_value<T>&>(*m_value).get();
 #endif
-    }
+  }
 
-    private:
-    void
-    ensure_value(const std::shared_ptr<const OptionDetails>& details)
+  private:
+  void
+  ensure_value(const std::shared_ptr<const OptionDetails>& details)
+  {
+    if (m_value == nullptr)
     {
-      if (m_value == nullptr)
-      {
-        m_value = details->make_storage();
-      }
+      m_value = details->make_storage();
     }
+  }
 
 
-    const std::string* m_long_name = nullptr;
-    // Holding this pointer is safe, since OptionValue's only exist in key-value pairs,
-    // where the key has the string we point to.
-    std::shared_ptr<Value> m_value{};
-    size_t m_count = 0;
-    bool m_default = false;
-  };
+  const std::string* m_long_name = nullptr;
+  // Holding this pointer is safe, since OptionValue's only exist in key-value pairs,
+  // where the key has the string we point to.
+  std::shared_ptr<Value> m_value{};
+  size_t m_count = 0;
+  bool m_default = false;
+};
 
-  class KeyValue
+class KeyValue
+{
+  public:
+  KeyValue(std::string key_, std::string value_)
+  : m_key(std::move(key_))
+  , m_value(std::move(value_))
   {
-    public:
-    KeyValue(std::string key_, std::string value_)
-    : m_key(std::move(key_))
-    , m_value(std::move(value_))
-    {
-    }
+  }
 
-    CXXOPTS_NODISCARD
-    const std::string&
-    key() const
-    {
-      return m_key;
-    }
+  CXXOPTS_NODISCARD
+  const std::string&
+  key() const
+  {
+    return m_key;
+  }
 
-    CXXOPTS_NODISCARD
-    const std::string&
-    value() const
-    {
-      return m_value;
-    }
+  CXXOPTS_NODISCARD
+  const std::string&
+  value() const
+  {
+    return m_value;
+  }
 
-    template <typename T>
-    T
-    as() const
-    {
-      T result;
-      values::parse_value(m_value, result);
-      return result;
-    }
+  template <typename T>
+  T
+  as() const
+  {
+    T result;
+    values::parse_value(m_value, result);
+    return result;
+  }
 
-    private:
-    std::string m_key;
-    std::string m_value;
-  };
+  private:
+  std::string m_key;
+  std::string m_value;
+};
 
-  using ParsedHashMap = std::unordered_map<size_t, OptionValue>;
-  using NameHashMap = std::unordered_map<std::string, size_t>;
+using ParsedHashMap = std::unordered_map<size_t, OptionValue>;
+using NameHashMap = std::unordered_map<std::string, size_t>;
 
-  class ParseResult
+class ParseResult
+{
+  public:
+  class Iterator
   {
     public:
-    class Iterator
-    {
-      public:
-      using iterator_category = std::forward_iterator_tag;
-      using value_type = KeyValue;
-      using difference_type = void;
-      using pointer = const KeyValue*;
-      using reference = const KeyValue&;
-
-      Iterator() = default;
-      Iterator(const Iterator&) = default;
-
-      Iterator(const ParseResult *pr, bool end=false)
-      : m_pr(pr)
-      , m_iter(end? pr->m_defaults.end(): pr->m_sequential.begin())
-      {
-      }
-
-      Iterator& operator++()
-      {
-        ++m_iter;
-        if(m_iter == m_pr->m_sequential.end())
-        {
-          m_iter = m_pr->m_defaults.begin();
-          return *this;
-        }
-        return *this;
-      }
-
-      Iterator operator++(int)
-      {
-        Iterator retval = *this;
-        ++(*this);
-        return retval;
-      }
-
-      bool operator==(const Iterator& other) const
-      {
-        return m_iter == other.m_iter;
-      }
+    using iterator_category = std::forward_iterator_tag;
+    using value_type = KeyValue;
+    using difference_type = void;
+    using pointer = const KeyValue*;
+    using reference = const KeyValue&;
 
-      bool operator!=(const Iterator& other) const
-      {
-        return !(*this == other);
-      }
+    Iterator() = default;
+    Iterator(const Iterator&) = default;
 
-      const KeyValue& operator*()
-      {
-        return *m_iter;
-      }
+    Iterator(const ParseResult *pr, bool end=false)
+    : m_pr(pr)
+    , m_iter(end? pr->m_defaults.end(): pr->m_sequential.begin())
+    {
+    }
 
-      const KeyValue* operator->()
+    Iterator& operator++()
+    {
+      ++m_iter;
+      if(m_iter == m_pr->m_sequential.end())
       {
-        return m_iter.operator->();
+        m_iter = m_pr->m_defaults.begin();
+        return *this;
       }
+      return *this;
+    }
 
-      private:
-      const ParseResult* m_pr;
-      std::vector<KeyValue>::const_iterator m_iter;
-    };
-
-    ParseResult() = default;
-    ParseResult(const ParseResult&) = default;
-
-    ParseResult(NameHashMap&& keys, ParsedHashMap&& values, std::vector<KeyValue> sequential, 
-            std::vector<KeyValue> default_opts, std::vector<std::string>&& unmatched_args)
-    : m_keys(std::move(keys))
-    , m_values(std::move(values))
-    , m_sequential(std::move(sequential))
-    , m_defaults(std::move(default_opts))
-    , m_unmatched(std::move(unmatched_args))
+    Iterator operator++(int)
     {
+      Iterator retval = *this;
+      ++(*this);
+      return retval;
     }
 
-    ParseResult& operator=(ParseResult&&) = default;
-    ParseResult& operator=(const ParseResult&) = default;
-
-    Iterator
-    begin() const
+    bool operator==(const Iterator& other) const
     {
-      return Iterator(this);
+      return m_iter == other.m_iter;
     }
 
-    Iterator
-    end() const
+    bool operator!=(const Iterator& other) const
     {
-      return Iterator(this, true);
+      return !(*this == other);
     }
 
-    size_t
-    count(const std::string& o) const
+    const KeyValue& operator*()
     {
-      auto iter = m_keys.find(o);
-      if (iter == m_keys.end())
-      {
-        return 0;
-      }
-
-      auto viter = m_values.find(iter->second);
-
-      if (viter == m_values.end())
-      {
-        return 0;
-      }
-
-      return viter->second.count();
+      return *m_iter;
     }
 
-    const OptionValue&
-    operator[](const std::string& option) const
+    const KeyValue* operator->()
     {
-      auto iter = m_keys.find(option);
+      return m_iter.operator->();
+    }
 
-      if (iter == m_keys.end())
-      {
-        throw_or_mimic<option_not_present_exception>(option);
-      }
+    private:
+    const ParseResult* m_pr;
+    std::vector<KeyValue>::const_iterator m_iter;
+  };
 
-      auto viter = m_values.find(iter->second);
+  ParseResult() = default;
+  ParseResult(const ParseResult&) = default;
 
-      if (viter == m_values.end())
-      {
-        throw_or_mimic<option_not_present_exception>(option);
-      }
+  ParseResult(NameHashMap&& keys, ParsedHashMap&& values, std::vector<KeyValue> sequential,
+          std::vector<KeyValue> default_opts, std::vector<std::string>&& unmatched_args)
+  : m_keys(std::move(keys))
+  , m_values(std::move(values))
+  , m_sequential(std::move(sequential))
+  , m_defaults(std::move(default_opts))
+  , m_unmatched(std::move(unmatched_args))
+  {
+  }
 
-      return viter->second;
-    }
+  ParseResult& operator=(ParseResult&&) = default;
+  ParseResult& operator=(const ParseResult&) = default;
 
-    const std::vector<KeyValue>&
-    arguments() const
+  Iterator
+  begin() const
+  {
+    return Iterator(this);
+  }
+
+  Iterator
+  end() const
+  {
+    return Iterator(this, true);
+  }
+
+  size_t
+  count(const std::string& o) const
+  {
+    auto iter = m_keys.find(o);
+    if (iter == m_keys.end())
     {
-      return m_sequential;
+      return 0;
     }
 
-    const std::vector<std::string>&
-    unmatched() const
+    auto viter = m_values.find(iter->second);
+
+    if (viter == m_values.end())
     {
-      return m_unmatched;
+      return 0;
     }
 
-    const std::vector<KeyValue>&
-    defaults() const
+    return viter->second.count();
+  }
+
+  const OptionValue&
+  operator[](const std::string& option) const
+  {
+    auto iter = m_keys.find(option);
+
+    if (iter == m_keys.end())
     {
-      return m_defaults;
+      throw_or_mimic<option_not_present_exception>(option);
     }
 
-    const std::string
-    arguments_string() const
+    auto viter = m_values.find(iter->second);
+
+    if (viter == m_values.end())
     {
-      std::string result;
-      for(const auto& kv: m_sequential)
-      {
-        result += kv.key() + " = " + kv.value() + "\n";
-      }
-      for(const auto& kv: m_defaults)
-      {
-        result += kv.key() + " = " + kv.value() + " " + "(default)" + "\n";
-      }
-      return result;
+      throw_or_mimic<option_not_present_exception>(option);
     }
 
-    private:
-    NameHashMap m_keys{};
-    ParsedHashMap m_values{};
-    std::vector<KeyValue> m_sequential{};
-    std::vector<KeyValue> m_defaults{};
-    std::vector<std::string> m_unmatched{};
-  };
+    return viter->second;
+  }
 
-  struct Option
+  const std::vector<KeyValue>&
+  arguments() const
   {
-    Option
-    (
-      std::string opts,
-      std::string desc,
-      std::shared_ptr<const Value>  value = ::cxxopts::value<bool>(),
-      std::string arg_help = ""
-    )
-    : opts_(std::move(opts))
-    , desc_(std::move(desc))
-    , value_(std::move(value))
-    , arg_help_(std::move(arg_help))
-    {
-    }
+    return m_sequential;
+  }
 
-    std::string opts_;
-    std::string desc_;
-    std::shared_ptr<const Value> value_;
-    std::string arg_help_;
-  };
+  const std::vector<std::string>&
+  unmatched() const
+  {
+    return m_unmatched;
+  }
 
-  using OptionMap = std::unordered_map<std::string, std::shared_ptr<OptionDetails>>;
-  using PositionalList = std::vector<std::string>;
-  using PositionalListIterator = PositionalList::const_iterator;
+  const std::vector<KeyValue>&
+  defaults() const
+  {
+    return m_defaults;
+  }
 
-  class OptionParser
+  const std::string
+  arguments_string() const
   {
-    public:
-    OptionParser(const OptionMap& options, const PositionalList& positional, bool allow_unrecognised)
-    : m_options(options)
-    , m_positional(positional)
-    , m_allow_unrecognised(allow_unrecognised)
+    std::string result;
+    for(const auto& kv: m_sequential)
     {
+      result += kv.key() + " = " + kv.value() + "\n";
     }
+    for(const auto& kv: m_defaults)
+    {
+      result += kv.key() + " = " + kv.value() + " " + "(default)" + "\n";
+    }
+    return result;
+  }
 
-    ParseResult
-    parse(int argc, const char* const* argv);
+  private:
+  NameHashMap m_keys{};
+  ParsedHashMap m_values{};
+  std::vector<KeyValue> m_sequential{};
+  std::vector<KeyValue> m_defaults{};
+  std::vector<std::string> m_unmatched{};
+};
 
-    bool
-    consume_positional(const std::string& a, PositionalListIterator& next);
+struct Option
+{
+  Option
+  (
+    std::string opts,
+    std::string desc,
+    std::shared_ptr<const Value>  value = ::cxxopts::value<bool>(),
+    std::string arg_help = ""
+  )
+  : opts_(std::move(opts))
+  , desc_(std::move(desc))
+  , value_(std::move(value))
+  , arg_help_(std::move(arg_help))
+  {
+  }
 
-    void
-    checked_parse_arg
-    (
-      int argc,
-      const char* const* argv,
-      int& current,
-      const std::shared_ptr<OptionDetails>& value,
-      const std::string& name
-    );
+  std::string opts_;
+  std::string desc_;
+  std::shared_ptr<const Value> value_;
+  std::string arg_help_;
+};
 
-    void
-    add_to_option(OptionMap::const_iterator iter, const std::string& option, const std::string& arg);
+using OptionMap = std::unordered_map<std::string, std::shared_ptr<OptionDetails>>;
+using PositionalList = std::vector<std::string>;
+using PositionalListIterator = PositionalList::const_iterator;
 
-    void
-    parse_option
-    (
-      const std::shared_ptr<OptionDetails>& value,
-      const std::string& name,
-      const std::string& arg = ""
-    );
+class OptionParser
+{
+  public:
+  OptionParser(const OptionMap& options, const PositionalList& positional, bool allow_unrecognised)
+  : m_options(options)
+  , m_positional(positional)
+  , m_allow_unrecognised(allow_unrecognised)
+  {
+  }
 
-    void
-    parse_default(const std::shared_ptr<OptionDetails>& details);
+  ParseResult
+  parse(int argc, const char* const* argv);
 
-    void
-    parse_no_value(const std::shared_ptr<OptionDetails>& details);
+  bool
+  consume_positional(const std::string& a, PositionalListIterator& next);
 
-    private:
+  void
+  checked_parse_arg
+  (
+    int argc,
+    const char* const* argv,
+    int& current,
+    const std::shared_ptr<OptionDetails>& value,
+    const std::string& name
+  );
 
-    void finalise_aliases();
+  void
+  add_to_option(OptionMap::const_iterator iter, const std::string& option, const std::string& arg);
 
-    const OptionMap& m_options;
-    const PositionalList& m_positional;
+  void
+  parse_option
+  (
+    const std::shared_ptr<OptionDetails>& value,
+    const std::string& name,
+    const std::string& arg = ""
+  );
 
-    std::vector<KeyValue> m_sequential{};
-    std::vector<KeyValue> m_defaults{};
-    bool m_allow_unrecognised;
+  void
+  parse_default(const std::shared_ptr<OptionDetails>& details);
 
-    ParsedHashMap m_parsed{};
-    NameHashMap m_keys{};
-  };
+  void
+  parse_no_value(const std::shared_ptr<OptionDetails>& details);
 
-  class Options
+  private:
+
+  void finalise_aliases();
+
+  const OptionMap& m_options;
+  const PositionalList& m_positional;
+
+  std::vector<KeyValue> m_sequential{};
+  std::vector<KeyValue> m_defaults{};
+  bool m_allow_unrecognised;
+
+  ParsedHashMap m_parsed{};
+  NameHashMap m_keys{};
+};
+
+class Options
+{
+  public:
+
+  explicit Options(std::string program, std::string help_string = "")
+  : m_program(std::move(program))
+  , m_help_string(toLocalString(std::move(help_string)))
+  , m_custom_help("[OPTION...]")
+  , m_positional_help("positional parameters")
+  , m_show_positional(false)
+  , m_allow_unrecognised(false)
+  , m_width(76)
+  , m_tab_expansion(false)
+  , m_options(std::make_shared<OptionMap>())
   {
-    public:
+  }
 
-    explicit Options(std::string program, std::string help_string = "")
-    : m_program(std::move(program))
-    , m_help_string(toLocalString(std::move(help_string)))
-    , m_custom_help("[OPTION...]")
-    , m_positional_help("positional parameters")
-    , m_show_positional(false)
-    , m_allow_unrecognised(false)
-    , m_width(76)
-    , m_tab_expansion(false)
-    , m_options(std::make_shared<OptionMap>())
-    {
-    }
+  Options&
+  positional_help(std::string help_text)
+  {
+    m_positional_help = std::move(help_text);
+    return *this;
+  }
 
-    Options&
-    positional_help(std::string help_text)
-    {
-      m_positional_help = std::move(help_text);
-      return *this;
-    }
+  Options&
+  custom_help(std::string help_text)
+  {
+    m_custom_help = std::move(help_text);
+    return *this;
+  }
 
-    Options&
-    custom_help(std::string help_text)
-    {
-      m_custom_help = std::move(help_text);
-      return *this;
-    }
+  Options&
+  show_positional_help()
+  {
+    m_show_positional = true;
+    return *this;
+  }
 
-    Options&
-    show_positional_help()
-    {
-      m_show_positional = true;
-      return *this;
-    }
+  Options&
+  allow_unrecognised_options()
+  {
+    m_allow_unrecognised = true;
+    return *this;
+  }
 
-    Options&
-    allow_unrecognised_options()
-    {
-      m_allow_unrecognised = true;
-      return *this;
-    }
+  Options&
+  set_width(size_t width)
+  {
+    m_width = width;
+    return *this;
+  }
 
-    Options&
-    set_width(size_t width)
-    {
-      m_width = width;
-      return *this;
-    }
+  Options&
+  set_tab_expansion(bool expansion=true)
+  {
+    m_tab_expansion = expansion;
+    return *this;
+  }
 
-    Options&
-    set_tab_expansion(bool expansion=true)
-    {
-      m_tab_expansion = expansion;
-      return *this;
-    }
+  ParseResult
+  parse(int argc, const char* const* argv);
 
-    ParseResult
-    parse(int argc, const char* const* argv);
-
-    OptionAdder
-    add_options(std::string group = "");
-
-    void
-    add_options
-    (
-      const std::string& group,
-      std::initializer_list<Option> options
-    );
-
-    void
-    add_option
-    (
-      const std::string& group,
-      const Option& option
-    );
-
-    void
-    add_option
-    (
-      const std::string& group,
-      const std::string& s,
-      const std::string& l,
-      std::string desc,
-      const std::shared_ptr<const Value>& value,
-      std::string arg_help
-    );
-
-    //parse positional arguments into the given option
-    void
-    parse_positional(std::string option);
-
-    void
-    parse_positional(std::vector<std::string> options);
-
-    void
-    parse_positional(std::initializer_list<std::string> options);
-
-    template <typename Iterator>
-    void
-    parse_positional(Iterator begin, Iterator end) {
-      parse_positional(std::vector<std::string>{begin, end});
-    }
+  OptionAdder
+  add_options(std::string group = "");
+
+  void
+  add_options
+  (
+    const std::string& group,
+    std::initializer_list<Option> options
+  );
+
+  void
+  add_option
+  (
+    const std::string& group,
+    const Option& option
+  );
 
-    std::string
-    help(const std::vector<std::string>& groups = {}) const;
+  void
+  add_option
+  (
+    const std::string& group,
+    const std::string& s,
+    const std::string& l,
+    std::string desc,
+    const std::shared_ptr<const Value>& value,
+    std::string arg_help
+  );
 
-    std::vector<std::string>
-    groups() const;
+  //parse positional arguments into the given option
+  void
+  parse_positional(std::string option);
 
-    const HelpGroupDetails&
-    group_help(const std::string& group) const;
+  void
+  parse_positional(std::vector<std::string> options);
 
-    const std::string& program() const
-    {
-      return m_program;
-    }
+  void
+  parse_positional(std::initializer_list<std::string> options);
 
-    private:
+  template <typename Iterator>
+  void
+  parse_positional(Iterator begin, Iterator end) {
+    parse_positional(std::vector<std::string>{begin, end});
+  }
 
-    void
-    add_one_option
-    (
-      const std::string& option,
-      const std::shared_ptr<OptionDetails>& details
-    );
-
-    String
-    help_one_group(const std::string& group) const;
-
-    void
-    generate_group_help
-    (
-      String& result,
-      const std::vector<std::string>& groups
-    ) const;
-
-    void
-    generate_all_groups_help(String& result) const;
-
-    std::string m_program{};
-    String m_help_string{};
-    std::string m_custom_help{};
-    std::string m_positional_help{};
-    bool m_show_positional;
-    bool m_allow_unrecognised;
-    size_t m_width;
-    bool m_tab_expansion;
-
-    std::shared_ptr<OptionMap> m_options;
-    std::vector<std::string> m_positional{};
-    std::unordered_set<std::string> m_positional_set{};
-
-    //mapping from groups to help options
-    std::map<std::string, HelpGroupDetails> m_help{};
-  };
+  std::string
+  help(const std::vector<std::string>& groups = {}) const;
+
+  std::vector<std::string>
+  groups() const;
 
-  class OptionAdder
+  const HelpGroupDetails&
+  group_help(const std::string& group) const;
+
+  const std::string& program() const
   {
-    public:
+    return m_program;
+  }
 
-    OptionAdder(Options& options, std::string group)
-    : m_options(options), m_group(std::move(group))
-    {
-    }
+  private:
+
+  void
+  add_one_option
+  (
+    const std::string& option,
+    const std::shared_ptr<OptionDetails>& details
+  );
 
-    OptionAdder&
-    operator()
-    (
-      const std::string& opts,
-      const std::string& desc,
-      const std::shared_ptr<const Value>& value
-        = ::cxxopts::value<bool>(),
-      std::string arg_help = ""
-    );
+  String
+  help_one_group(const std::string& group) const;
 
-    private:
-    Options& m_options;
-    std::string m_group;
-  };
+  void
+  generate_group_help
+  (
+    String& result,
+    const std::vector<std::string>& groups
+  ) const;
+
+  void
+  generate_all_groups_help(String& result) const;
+
+  std::string m_program{};
+  String m_help_string{};
+  std::string m_custom_help{};
+  std::string m_positional_help{};
+  bool m_show_positional;
+  bool m_allow_unrecognised;
+  size_t m_width;
+  bool m_tab_expansion;
+
+  std::shared_ptr<OptionMap> m_options;
+  std::vector<std::string> m_positional{};
+  std::unordered_set<std::string> m_positional_set{};
+
+  //mapping from groups to help options
+  std::map<std::string, HelpGroupDetails> m_help{};
+};
+
+class OptionAdder
+{
+  public:
 
-  namespace
+  OptionAdder(Options& options, std::string group)
+  : m_options(options), m_group(std::move(group))
   {
-    constexpr size_t OPTION_LONGEST = 30;
-    constexpr size_t OPTION_DESC_GAP = 2;
+  }
 
-    String
-    format_option
-    (
-      const HelpOptionDetails& o
-    )
+  OptionAdder&
+  operator()
+  (
+    const std::string& opts,
+    const std::string& desc,
+    const std::shared_ptr<const Value>& value
+      = ::cxxopts::value<bool>(),
+    std::string arg_help = ""
+  );
+
+  private:
+  Options& m_options;
+  std::string m_group;
+};
+
+namespace {
+  constexpr size_t OPTION_LONGEST = 30;
+  constexpr size_t OPTION_DESC_GAP = 2;
+
+  String
+  format_option
+  (
+    const HelpOptionDetails& o
+  )
+  {
+    const auto& s = o.s;
+    const auto& l = o.l;
+
+    String result = "  ";
+
+    if (!s.empty())
+    {
+      result += "-" + toLocalString(s);
+      if (!l.empty())
+      {
+        result += ",";
+      }
+    }
+    else
+    {
+      result += "   ";
+    }
+
+    if (!l.empty())
     {
-      const auto& s = o.s;
-      const auto& l = o.l;
+      result += " --" + toLocalString(l);
+    }
 
-      String result = "  ";
+    auto arg = !o.arg_help.empty() ? toLocalString(o.arg_help) : "arg";
 
-      if (!s.empty())
+    if (!o.is_boolean)
+    {
+      if (o.has_implicit)
       {
-        result += "-" + toLocalString(s);
-        if (!l.empty())
-        {
-          result += ",";
-        }
+        result += " [=" + arg + "(=" + toLocalString(o.implicit_value) + ")]";
       }
       else
       {
-        result += "   ";
+        result += " " + arg;
       }
+    }
 
-      if (!l.empty())
-      {
-        result += " --" + toLocalString(l);
-      }
+    return result;
+  }
 
-      auto arg = !o.arg_help.empty() ? toLocalString(o.arg_help) : "arg";
+  String
+  format_description
+  (
+    const HelpOptionDetails& o,
+    size_t start,
+    size_t allowed,
+    bool tab_expansion
+  )
+  {
+    auto desc = o.desc;
 
-      if (!o.is_boolean)
+    if (o.has_default && (!o.is_boolean || o.default_value != "false"))
+    {
+      if(!o.default_value.empty())
       {
-        if (o.has_implicit)
-        {
-          result += " [=" + arg + "(=" + toLocalString(o.implicit_value) + ")]";
-        }
-        else
-        {
-          result += " " + arg;
-        }
+        desc += toLocalString(" (default: " + o.default_value + ")");
+      }
+      else
+      {
+        desc += toLocalString(" (default: \"\")");
       }
-
-      return result;
     }
 
-    String
-    format_description
-    (
-      const HelpOptionDetails& o,
-      size_t start,
-      size_t allowed,
-      bool tab_expansion
-    )
-    {
-      auto desc = o.desc;
+    String result;
 
-      if (o.has_default && (!o.is_boolean || o.default_value != "false"))
+    if (tab_expansion)
+    {
+      String desc2;
+      auto size = size_t{ 0 };
+      for (auto c = std::begin(desc); c != std::end(desc); ++c)
       {
-        if(!o.default_value.empty())
+        if (*c == '\n')
         {
-          desc += toLocalString(" (default: " + o.default_value + ")");
+          desc2 += *c;
+          size = 0;
         }
-        else
+        else if (*c == '\t')
         {
-          desc += toLocalString(" (default: \"\")");
+          auto skip = 8 - size % 8;
+          stringAppend(desc2, skip, ' ');
+          size += skip;
         }
-      }
-
-      String result;
-
-      if (tab_expansion)
-      {
-        String desc2;
-        auto size = size_t{ 0 };
-        for (auto c = std::begin(desc); c != std::end(desc); ++c)
+        else
         {
-          if (*c == '\n')
-          {
-            desc2 += *c;
-            size = 0;
-          }
-          else if (*c == '\t')
-          {
-            auto skip = 8 - size % 8;
-            stringAppend(desc2, skip, ' ');
-            size += skip;
-          }
-          else
-          {
-            desc2 += *c;
-            ++size;
-          }
+          desc2 += *c;
+          ++size;
         }
-        desc = desc2;
       }
+      desc = desc2;
+    }
 
-      desc += " ";
+    desc += " ";
 
-      auto current = std::begin(desc);
-      auto previous = current;
-      auto startLine = current;
-      auto lastSpace = current;
+    auto current = std::begin(desc);
+    auto previous = current;
+    auto startLine = current;
+    auto lastSpace = current;
 
-      auto size = size_t{};
+    auto size = size_t{};
 
-      bool appendNewLine;
-      bool onlyWhiteSpace = true;
+    bool appendNewLine;
+    bool onlyWhiteSpace = true;
 
-      while (current != std::end(desc))
+    while (current != std::end(desc))
+    {
+      appendNewLine = false;
+
+      if (std::isblank(*previous))
       {
-        appendNewLine = false;
+        lastSpace = current;
+      }
 
-        if (std::isblank(*previous))
-        {
-          lastSpace = current;
-        }
+      if (!std::isblank(*current))
+      {
+        onlyWhiteSpace = false;
+      }
 
-        if (!std::isblank(*current))
-        {
-          onlyWhiteSpace = false;
-        }
+      while (*current == '\n')
+      {
+        previous = current;
+        ++current;
+        appendNewLine = true;
+      }
 
-        while (*current == '\n')
+      if (!appendNewLine && size >= allowed)
+      {
+        if (lastSpace != startLine)
         {
+          current = lastSpace;
           previous = current;
-          ++current;
-          appendNewLine = true;
         }
+        appendNewLine = true;
+      }
 
-        if (!appendNewLine && size >= allowed)
-        {
-          if (lastSpace != startLine)
-          {
-            current = lastSpace;
-            previous = current;
-          }
-          appendNewLine = true;
-        }
+      if (appendNewLine)
+      {
+        stringAppend(result, startLine, current);
+        startLine = current;
+        lastSpace = current;
 
-        if (appendNewLine)
+        if (*previous != '\n')
         {
-          stringAppend(result, startLine, current);
-          startLine = current;
-          lastSpace = current;
-
-          if (*previous != '\n')
-          {
-            stringAppend(result, "\n");
-          }
-
-          stringAppend(result, start, ' ');
+          stringAppend(result, "\n");
+        }
 
-          if (*previous != '\n')
-          {
-            stringAppend(result, lastSpace, current);
-          }
+        stringAppend(result, start, ' ');
 
-          onlyWhiteSpace = true;
-          size = 0;
+        if (*previous != '\n')
+        {
+          stringAppend(result, lastSpace, current);
         }
 
-        previous = current;
-        ++current;
-        ++size;
+        onlyWhiteSpace = true;
+        size = 0;
       }
 
-      //append whatever is left but ignore whitespace
-      if (!onlyWhiteSpace)
-      {
-        stringAppend(result, startLine, previous);
-      }
+      previous = current;
+      ++current;
+      ++size;
+    }
 
-      return result;
+    //append whatever is left but ignore whitespace
+    if (!onlyWhiteSpace)
+    {
+      stringAppend(result, startLine, previous);
     }
-  } // namespace
+
+    return result;
+  }
+} // namespace
 
 inline
 void