Add integer, serializable, CMake version.

include/xgboost/base.h

@@ -69,6 +69,12 @@
 #define XGBOOST_PARALLEL_STABLE_SORT(X, Y, Z) std::stable_sort((X), (Y), (Z))
 #endif  // GLIBC VERSION
 
+#if defined(__GNUC__)
+#define XGBOOST_EXPECT(cond, ret)  __builtin_expect((cond), (ret))
+#else
+#define XGBOOST_EXPECT(cond, ret) (cond)
+#endif  // defined(__GNUC__)
+
 /*!
  * \brief Tag function as usable by device
  */

include/xgboost/json.h

@@ -4,8 +4,8 @@
 #ifndef XGBOOST_JSON_H_
 #define XGBOOST_JSON_H_
 
+#include <dmlc/io.h>  // deprecated
 #include <xgboost/logging.h>
-
 #include <string>
 
 #include <map>
@@ -185,7 +185,7 @@ class JsonNumber : public Value {
 
  public:
   JsonNumber() : Value(ValueKind::Number) {}
-  JsonNumber(double value) : Value(ValueKind::Number) {  // NOLINT
+  JsonNumber(Float value) : Value(ValueKind::Number) {  // NOLINT
     number_ = value;
   }
 
@@ -198,6 +198,7 @@ class JsonNumber : public Value {
   Float const& getNumber() const & { return number_; }
   Float&       getNumber()       & { return number_; }
 
+
   bool operator==(Value const& rhs) const override;
   Value& operator=(Value const& rhs) override;
 
@@ -206,6 +207,34 @@ class JsonNumber : public Value {
   }
 };
 
+class JsonInteger : public Value {
+ public:
+  using Int = int64_t;
+
+ private:
+  Int integer_;
+
+ public:
+  JsonInteger() : Value(ValueKind::Integer), integer_{0} {}
+  template <typename IntT, typename std::enable_if<std::is_same<IntT, Int>::value>::type* = nullptr>
+  JsonInteger(IntT value) : Value(ValueKind::Integer), integer_{value} {}
+
+  Json& operator[](std::string const & key) override;
+  Json& operator[](int ind) override;
+
+  bool operator==(Value const& rhs) const override;
+  Value& operator=(Value const& rhs) override;
+
+  Int const& getInteger() &&      { return integer_; }
+  Int const& getInteger() const & { return integer_; }
+  Int& getInteger() &             { return integer_; }
+  void Save(JsonWriter* writer) override;
+
+  static bool isClassOf(Value const* value) {
+    return value->Type() == ValueKind::Integer;
+  }
+};
+
 class JsonNull : public Value {
  public:
   JsonNull() : Value(ValueKind::Null) {}
@@ -256,15 +285,16 @@ class JsonBoolean : public Value {
 };
 
 struct StringView {
-  char const* str_;
+  using CharT = char;  // unsigned char
+  CharT const* str_;
   size_t size_;
 
  public:
   StringView() = default;
-  StringView(char const* str, size_t size) : str_{str}, size_{size} {}
+  StringView(CharT const* str, size_t size) : str_{str}, size_{size} {}
 
-  char const& operator[](size_t p) const { return str_[p]; }
-  char const& at(size_t p) const {  // NOLINT
+  CharT const& operator[](size_t p) const { return str_[p]; }
+  CharT const& at(size_t p) const {  // NOLINT
     CHECK_LT(p, size_);
     return str_[p];
   }
@@ -319,6 +349,13 @@ class Json {
     return *this;
   }
 
+  // integer
+  explicit Json(JsonInteger integer) : ptr_{new JsonInteger(integer)} {}
+  Json& operator=(JsonInteger integer) {
+    ptr_.reset(new JsonInteger(std::move(integer)));
+    return *this;
+  }
+
   // array
   explicit Json(JsonArray list) :
       ptr_ {new JsonArray(std::move(list))} {}
@@ -410,10 +447,24 @@ JsonNumber::Float& GetImpl(T& val) {  // NOLINT
 template <typename T,
           typename std::enable_if<
             std::is_same<T, JsonNumber const>::value>::type* = nullptr>
-double const& GetImpl(T& val) {  // NOLINT
+JsonNumber::Float const& GetImpl(T& val) {  // NOLINT
   return val.getNumber();
 }
 
+// Integer
+template <typename T,
+          typename std::enable_if<
+            std::is_same<T, JsonInteger>::value>::type* = nullptr>
+JsonInteger::Int& GetImpl(T& val) {  // NOLINT
+  return val.getInteger();
+}
+template <typename T,
+          typename std::enable_if<
+            std::is_same<T, JsonInteger const>::value>::type* = nullptr>
+JsonInteger::Int const& GetImpl(T& val) {  // NOLINT
+  return val.getInteger();
+}
+
 // String
 template <typename T,
           typename std::enable_if<
@@ -502,6 +553,7 @@ auto get(U& json) -> decltype(detail::GetImpl(*Cast<T>(&json.GetValue())))& { //
 using Object  = JsonObject;
 using Array   = JsonArray;
 using Number  = JsonNumber;
+using Integer = JsonInteger;
 using Boolean = JsonBoolean;
 using String  = JsonString;
 using Null    = JsonNull;
@@ -525,6 +577,36 @@ inline std::map<std::string, std::string> fromJson(std::map<std::string, Json> c
   }
   return res;
 }
-
 }  // namespace xgboost
+
+#include <rabit/rabit.h>
+
+namespace xgboost {
+
+struct Serializable : public rabit::Serializable {
+  virtual ~Serializable() = default;
+  /*!
+  * \brief load the model from a stream
+  * \param fi stream where to load the model from
+  */
+  virtual void Load(dmlc::Stream *fi) override = 0;
+  /*!
+  * \brief saves the model to a stream
+  * \param fo stream where to save the model to
+  */
+  virtual void Save(dmlc::Stream *fo) const override = 0;
+
+  /*!
+   * \brief load the model from a json object
+   * \param in json object where to load the model from
+   */
+  virtual void Load(Json const& in) = 0;
+  /*!
+   * \breif saves the model to a json object
+   * \param out json container where to save the model to
+   */
+  virtual void Save(Json* out) const = 0;
+};
+}      // namespace xgboost
+
 #endif  // XGBOOST_JSON_H_

include/xgboost/json_io.h

@@ -80,10 +80,14 @@ class JsonReader {
     explicit SourceLocation(size_t pos) : pos_{pos} {}
     size_t  Pos()  const { return pos_; }
 
-    SourceLocation& Forward(char c = 0) {
+    SourceLocation& Forward() {
       pos_++;
       return *this;
     }
+    SourceLocation& Forward(uint32_t n) {
+      pos_ += n;
+      return *this;
+    }
   } cursor_;
 
   StringView raw_str_;
@@ -207,6 +211,7 @@ class JsonWriter {
   virtual void Visit(JsonArray  const* arr);
   virtual void Visit(JsonObject const* obj);
   virtual void Visit(JsonNumber const* num);
+  virtual void Visit(JsonInteger const* num);
   virtual void Visit(JsonRaw    const* raw);
   virtual void Visit(JsonNull   const* null);
   virtual void Visit(JsonString const* str);

include/xgboost/learner.h

@@ -8,8 +8,6 @@
 #ifndef XGBOOST_LEARNER_H_
 #define XGBOOST_LEARNER_H_
 
-#include <rabit/rabit.h>
-
 #include <xgboost/base.h>
 #include <xgboost/gbm.h>
 #include <xgboost/metric.h>
@@ -42,7 +40,7 @@ namespace xgboost {
  *
  *  \endcode
  */
-class Learner : public rabit::Serializable {
+class Learner : public Serializable {
  public:
   /*! \brief virtual destructor */
   ~Learner() override = default;
@@ -51,14 +49,14 @@ class Learner : public rabit::Serializable {
    */
   virtual void Configure() = 0;
 
-  virtual void Load(Json const& in) = 0;
+  virtual void Load(Json const& in) override = 0;
   /*!
    * \brief load model from stream
    * \param fi input stream.
    */
   void Load(dmlc::Stream* fi) override = 0;
 
-  virtual void Save(Json* out) const = 0;
+  virtual void Save(Json* out) const override = 0;
   /*!
    * \brief save model to stream.
    * \param fo output stream