Const modifier to table get and some array operations

include/array.h

@@ -99,6 +99,25 @@ public:
      */
     const Field &get(uint8_t index);
 
+    /**
+     *  Get number of elements on this array
+     *
+     *  @return array size
+     */
+    uint32_t count() const;
+
+    /**
+     * Remove last element from array
+     */
+    void pop_back();
+
+    /**
+     * Add field to end of array
+     *
+     * @param value
+     */
+    void push_back(const Field &value);
+
     /**
      *  Get a field
      *

include/table.h

@@ -109,7 +109,7 @@ public:
      *  @param  name    field name
      *  @return         the field value
      */
-    const Field &get(const std::string &name);
+    const Field &get(const std::string &name) const;
 
     /**
      *  Get a field

src/array.cpp

@@ -70,6 +70,21 @@ const Field &Array::get(uint8_t index)
     return *_fields[index];
 }
 
+uint32_t Array::count() const
+{
+  return _fields.size();
+}
+
+void Array::pop_back()
+{
+    _fields.pop_back();
+}
+
+void Array::push_back(const Field& value)
+{
+    _fields.push_back(std::shared_ptr<Field>(value.clone()));
+}
+
 /**
  *  Get the size this field will take when
  *  encoded in the AMQP wire-frame format

src/table.cpp

@@ -97,7 +97,7 @@ Table &Table::operator=(Table &&table)
  *  @param  name    field name
  *  @return         the field value
  */
-const Field &Table::get(const std::string &name)
+const Field &Table::get(const std::string &name) const
 {
     // we need an empty string
     static ShortString empty;