Replaced the accessors that return optional string_view objects with two separate functions.

src/detail/uri_resolve.cpp

@@ -65,15 +65,15 @@ uri::string_type remove_dot_segments(uri::string_view path) {
 uri::string_type merge_paths(const uri& base, const uri& reference) {
   uri::string_type result;
 
-  if (!base.path() || base.path()->empty()) {
+  if (!base.has_path() || base.path().empty()) {
     result = "/";
   } else {
-    const auto& base_path = base.path().value();
+    const auto& base_path = base.path();
     auto last_slash = network_boost::find_last(base_path, "/");
     result.append(std::begin(base_path), std::end(last_slash));
   }
-  if (reference.path()) {
-    result.append(reference.path()->to_string());
+  if (reference.has_path()) {
+    result.append(reference.path().to_string());
   }
   return remove_dot_segments(std::move(result));
 }

src/network/uri/uri.hpp

@@ -119,7 +119,7 @@ class uri {
 
  public:
   /**
-   * \brief Constructor.
+   * \brief Default constructor.
    */
   uri();
 
@@ -205,78 +205,135 @@ class uri {
    *        underlying sequence.
    * \return An iterator starting at the first element.
    */
-  const_iterator begin() const;
+  const_iterator begin() const noexcept;
 
   /**
    * \brief Returns an iterator at the end + 1th element in the
    *        underlying sequence.
    * \return An iterator starting at the end + 1th element.
    */
-  const_iterator end() const;
+  const_iterator end() const noexcept;
+
+  /**
+   * \brief Tests whether this URI has a scheme component.
+   * \return \c true if the URI has a scheme, \c false otherwise.
+   */
+  bool has_scheme() const noexcept;
 
   /**
    * \brief Returns the URI scheme.
-   * \return The scheme, if it exists, or nullopt.
+   * \return The scheme.
+   * \pre has_scheme()
+   */
+  string_view scheme() const noexcept;
+
+  /**
+   * \brief Tests whether this URI has a user info component.
+   * \return \c true if the URI has a user info, \c false otherwise.
    */
-  optional<string_view> scheme() const;
+  bool has_user_info() const noexcept;
 
   /**
    * \brief Returns the URI user info.
-   * \return The user info, if it exists, or nullopt.
+   * \return The user info.
+   * \pre has_user_info()
    */
-  optional<string_view> user_info() const;
+  string_view user_info() const noexcept;
+
+  /**
+   * \brief Tests whether this URI has a host component.
+   * \return \c true if the URI has a host, \c false otherwise.
+   */
+  bool has_host() const noexcept;
 
   /**
    * \brief Returns the URI host.
-   * \return The host, if it exists, or nullopt.
+   * \return The host.
+   * \pre has_host()
    */
-  optional<string_view> host() const;
+  string_view host() const noexcept;
+
+  /**
+   * \brief Tests whether this URI has a port component.
+   * \return \c true if the URI has a port, \c false otherwise.
+   */
+  bool has_port() const noexcept;
 
   /**
    * \brief Returns the URI port.
-   * \return The port, if it exists, or nullopt.
+   * \return The port.
+   * \pre has_port()
    */
-  optional<string_view> port() const;
+  string_view port() const noexcept;
 
   /**
    * \brief Returns the URI port as an integer.
-   * \return The port, if it exists, or nullopt.
+   * \return The port number.
+   * \pre has_port()
    */
   template <typename IntT>
-  optional<IntT> port(typename std::is_integral<IntT>::type * = 0) const {
-    if (auto p = port()) {
-      try {
-        return std::stoi(string_type(std::begin(*p), std::end(*p)));
-      } catch (std::exception &) {
-        return optional<IntT>();
-      }
+  IntT port(typename std::is_integral<IntT>::type * = 0) const {
+    assert(has_port());
+
+    auto p = port();
+    try {
+      return std::stoi(port().to_string());
+    }
+    catch (std::exception &) {
+      assert(!"Unable to parse port number.");
     }
-    return optional<IntT>();
   }
 
+  /**
+   * \brief Tests whether this URI has a path component.
+   * \return \c true if the URI has a path, \c false otherwise.
+   */
+  bool has_path() const noexcept;
+
   /**
    * \brief Returns the URI path.
-   * \return The path, if it exists, or nullopt.
+   * \return The path.
+   * \pre has_path()
+   */
+  string_view path() const noexcept;
+
+  /**
+   * \brief Tests whether this URI has a query component.
+   * \return \c true if the URI has a query, \c false otherwise.
    */
-  optional<string_view> path() const;
+  bool has_query() const noexcept;
 
   /**
    * \brief Returns the URI query.
-   * \return The query, if it exists, or nullopt.
+   * \return The query.
+   * \pre has_query()
    */
-  optional<string_view> query() const;
+  string_view query() const noexcept;
+
+  /**
+   * \brief Tests whether this URI has a fragment component.
+   * \return \c true if the URI has a fragment, \c false otherwise.
+   */
+  bool has_fragment() const noexcept;
 
   /**
    * \brief Returns the URI fragment.
-   * \return The fragment, if it exists, or nullopt.
+   * \return The fragment.
+   * \pre has_fragment()
+   */
+  string_view fragment() const noexcept;
+
+  /**
+   * \brief Tests whether this URI has a valid authority.
+   * \return \c true if the URI has an authority, \c false otherwise.
    */
-  optional<string_view> fragment() const;
+  bool has_authority() const noexcept;
 
   /**
    * \brief Returns the URI authority.
-   * \return The authority, if it exists, or nullopt.
+   * \return The authority.
    */
-  optional<string_view> authority() const;
+  string_view authority() const noexcept;
 
 #if !defined(NETWORK_URI_MSVC)
   /**
@@ -333,14 +390,14 @@ class uri {
    * \brief Checks if the uri is absolute, i.e. it has a scheme.
    * \returns \c true if it is absolute, \c false if it is relative.
    */
-  bool is_absolute() const;
+  bool is_absolute() const noexcept;
 
   /**
    * \brief Checks if the uri is opaque, i.e. if it doesn't have an
    *        authority.
    * \returns \c true if it is opaque, \c false if it is hierarchical.
    */
-  bool is_opaque() const;
+  bool is_opaque() const noexcept;
 
   /**
    * \brief Normalizes a uri object at a given level in the