Add as_string() casting numbers to strings

json11.cpp

@@ -169,6 +169,7 @@ protected:
 };
 
 class JsonDouble final : public Value<Json::NUMBER, double> {
+    string as_string() const { return std::to_string(m_value); }
     bool bool_value() const override { return m_value != 0; }
     double number_value() const override { return static_cast<double>(m_value); }
     int64_ int64_value() const override { return static_cast<int64_>(m_value); }
@@ -180,6 +181,7 @@ public:
 };
 
 class JsonInt64 final : public Value<Json::NUMBER, int64_> {
+    string as_string() const { return std::to_string(m_value); }
     bool bool_value() const override { return m_value != 0; }
     double number_value() const override { return static_cast<double>(m_value); }
     int64_ int64_value() const override { return static_cast<int64_>(m_value); }
@@ -191,6 +193,7 @@ public:
 };
 
 class JsonUInt64 final : public Value<Json::NUMBER, uint64_> {
+    string as_string() const { return std::to_string(m_value); }
     bool bool_value() const override { return m_value != 0; }
     double number_value() const override { return static_cast<double>(m_value); }
     int64_ int64_value() const override { return static_cast<int64_>(m_value); }
@@ -208,6 +211,7 @@ public:
 };
 
 class JsonString final : public Value<Json::STRING, string> {
+    string as_string() const { return m_value; }
     const string &string_value() const override { return m_value; }
     bool bool_value() const override { return m_value != "" && m_value != "0"; }
     double number_value() const override { size_t pos = 0; double v = std::stod(m_value, &pos); if (pos < m_value.length()) { v = 0; } return v; }
@@ -291,6 +295,7 @@ double Json::number_value()                       const { return m_ptr->number_v
 int64_ Json::int64_value()                        const { return m_ptr->int64_value();  }
 uint64_ Json::uint64_value()                        const { return m_ptr->uint64_value();  }
 bool Json::bool_value()                           const { return m_ptr->bool_value();   }
+string Json::as_string()                          const { return m_ptr->as_string(); }
 const string & Json::string_value()               const { return m_ptr->string_value(); }
 const vector<Json> & Json::array_items()          const { return m_ptr->array_items();  }
 const map<string, Json> & Json::object_items()    const { return m_ptr->object_items(); }
@@ -301,6 +306,7 @@ double                    JsonValue::number_value()              const { return
 int64_                    JsonValue::int64_value()               const { return 0; }
 uint64_                   JsonValue::uint64_value()              const { return 0; }
 bool                      JsonValue::bool_value()                const { return false; }
+string                    JsonValue::as_string()                 const { return statics().empty_string; }
 const string &            JsonValue::string_value()              const { return statics().empty_string; }
 const vector<Json> &      JsonValue::array_items()               const { return statics().empty_vector; }
 const map<string, Json> & JsonValue::object_items()              const { return statics().empty_map; }

json11.hpp

@@ -142,13 +142,17 @@ public:
     bool is_array()  const { return type() == ARRAY; }
     bool is_object() const { return type() == OBJECT; }
 
-    // Return the enclosed value if this is a number, 0 otherwise. Note that json11 does not
+    // Return the enclosed value if this is a number, parse a string if it's a string,
+    // return 0 if neither a number nor a parseable string. Note that json11 does not
     // distinguish between integer and non-integer numbers - number_value() and int64_value()
     // can both be applied to a NUMBER-typed object.
     double number_value() const;
     int64_ int64_value() const;
     uint64_ uint64_value() const;
 
+    // Return the enclosed string if this is a string, "" otherwise.
+    std::string as_string() const;
+
     // Return the enclosed value if this is a boolean, false otherwise.
     bool bool_value() const;
     // Return the enclosed string if this is a string, "" otherwise.
@@ -235,6 +239,7 @@ protected:
     virtual uint64_ uint64_value() const;
     virtual bool bool_value() const;
     virtual const std::string &string_value() const;
+    virtual std::string as_string() const;
     virtual const Json::array &array_items() const;
     virtual const Json &operator[](size_t i) const;
     virtual const Json::object &object_items() const;