moved class into "nlohmann" namespace

- fixed issue #9
- also removed std::mutex member variable
- also added “std::” prefix to size_t variables

README.md

@@ -30,6 +30,9 @@ All you need to do is add
 
 ```cpp
 #include "json.h"
+
+// for convenience
+using json = nlohmann::json;
 ```
 
 to the files you want to use JSON objects. Furthermore, you need to compile the file `json.cc` and link it to your binaries. Do not forget to set the necessary switches to enable C++11 (e.g., `-std=c++11` for GCC and Clang).

benchmark/parse.cc

@@ -2,7 +2,7 @@
 
 int main()
 {
-    json j;
+    nlohmann::json j;
     j << std::cin;
     return 0;
 }

src/json.cc

@@ -12,17 +12,12 @@
 #include "json.h"
 
 #include <cctype>     // std::isdigit, std::isspace
-#include <cstddef>    // size_t
+#include <cstddef>    // std::size_t
 #include <stdexcept>  // std::runtime_error
 #include <utility>    // std::swap, std::move
 
-
+namespace nlohmann
-////////////////////
+{
-// STATIC MEMBERS //
-////////////////////
-
-std::mutex json::token_;
-
 
 ///////////////////////////////////
 // CONSTRUCTORS OF UNION "value" //
@@ -639,8 +634,6 @@ void json::push_back(const json& o)
         throw std::runtime_error("cannot add element to " + type_name());
     }
 
-    std::lock_guard<std::mutex> lg(token_);
-
     // transform null object into an array
     if (type_ == value_type::null)
     {
@@ -676,8 +669,6 @@ void json::push_back(json&& o)
         throw std::runtime_error("cannot add element to " + type_name());
     }
 
-    std::lock_guard<std::mutex> lg(token_);
-
     // transform null object into an array
     if (type_ == value_type::null)
     {
@@ -804,10 +795,8 @@ json& json::operator[](const int index)
                                 std::to_string(index) + " to " + type_name());
     }
 
-    std::lock_guard<std::mutex> lg(token_);
-
     // return reference to element from array at given index
-    return (*value_.array)[static_cast<size_t>(index)];
+    return (*value_.array)[static_cast<std::size_t>(index)];
 }
 
 /*!
@@ -836,7 +825,7 @@ const json& json::operator[](const int index) const
     }
 
     // return element from array at given index
-    return (*value_.array)[static_cast<size_t>(index)];
+    return (*value_.array)[static_cast<std::size_t>(index)];
 }
 
 /*!
@@ -865,10 +854,8 @@ json& json::at(const int index)
                                 std::to_string(index) + " to " + type_name());
     }
 
-    std::lock_guard<std::mutex> lg(token_);
-
     // return reference to element from array at given index
-    return value_.array->at(static_cast<size_t>(index));
+    return value_.array->at(static_cast<std::size_t>(index));
 }
 
 /*!
@@ -898,7 +885,7 @@ const json& json::at(const int index) const
     }
 
     // return element from array at given index
-    return value_.array->at(static_cast<size_t>(index));
+    return value_.array->at(static_cast<std::size_t>(index));
 }
 
 /*!
@@ -924,8 +911,6 @@ key.
 */
 json& json::operator[](const char* key)
 {
-    std::lock_guard<std::mutex> lg(token_);
-
     // implicitly convert null to object
     if (type_ == value_type::null)
     {
@@ -1006,8 +991,6 @@ key.
 */
 json& json::at(const char* key)
 {
-    std::lock_guard<std::mutex> lg(token_);
-
     // this function operator only works for objects
     if (type_ != value_type::object)
     {
@@ -1061,7 +1044,7 @@ Returns the size of the JSON object.
 
 @invariant The size is reported as 0 if and only if empty() would return true.
 */
-size_t json::size() const noexcept
+std::size_t json::size() const noexcept
 {
     switch (type_)
     {
@@ -2105,6 +2088,8 @@ void json::parser::expect(const char c)
     }
 }
 
+}
+
 /*!
 This operator implements a user-defined string literal for JSON objects. It can
 be used by adding \p "_json" to a string literal and returns a JSON object if
@@ -2113,7 +2098,7 @@ no parse error occurred.
 @param s  a string representation of a JSON object
 @return a JSON object
 */
-json operator "" _json(const char* s, size_t)
+nlohmann::json operator "" _json(const char* s, std::size_t)
 {
-    return json::parse(s);
+    return nlohmann::json::parse(s);
 }

src/json.h

@@ -14,10 +14,12 @@
 #include <initializer_list>  // std::initializer_list
 #include <iostream>          // std::istream, std::ostream
 #include <map>               // std::map
-#include <mutex>             // std::mutex
 #include <string>            // std::string
 #include <vector>            // std::vector
 
+namespace nlohmann
+{
+
 /*!
 @brief JSON for Modern C++
 
@@ -274,7 +276,7 @@ class json
     const json& at(const char*) const;
 
     /// return the number of stored values
-    size_t size() const noexcept;
+    std::size_t size() const noexcept;
     /// checks whether object is empty
     bool empty() const noexcept;
     /// removes all elements from compounds and resets values to default
@@ -317,10 +319,6 @@ class json
     /// the payload
     value value_ {};
 
-  private:
-    /// mutex to guard payload
-    static std::mutex token_;
-
   public:
     /// an iterator
     class iterator
@@ -431,9 +429,11 @@ class json
         /// the current character
         char current_ {};
         /// the position inside the input buffer
-        size_t pos_ = 0;
+        std::size_t pos_ = 0;
     };
 };
 
+}
+
 /// user-defined literal operator to create JSON objects from strings
-json operator "" _json(const char*, size_t);
+nlohmann::json operator "" _json(const char*, std::size_t);

test/json_unit.cc

@@ -3,6 +3,8 @@
 
 #include "json.h"
 
+using json = nlohmann::json;
+
 TEST_CASE("array")
 {
     SECTION("Basics")