Add support for printing std containers (#207)

Author: SergiusTheBest

include/plog/Record.h

@@ -78,12 +78,43 @@ namespace plog
             plog::detail::operator<<(stream, data.c_str());
         }
 
+        // Print `std::pair`
+        template<class T1, class T2>
+        inline void operator<<(util::nostringstream& stream, const std::pair<T1, T2>& data)
+        {
+            stream << data.first;
+            stream << ":";
+            stream << data.second;
+        }
+
 #if defined(__clang__) || !defined(__GNUC__) || __GNUC__ > 4 || __GNUC__ == 4 && __GNUC_MINOR__ > 4 // skip for GCC < 4.5 due to https://gcc.gnu.org/bugzilla/show_bug.cgi?id=38600
+        // Print data that can be casted to `std::basic_string`. `+ sizeof(T*)` is required for GCC 4.5-4.7.
         template<typename T>
         inline typename meta::enableIf<!!(sizeof(static_cast<std::basic_string<util::nchar> >(meta::declval<T>())) + sizeof(T*)), void>::type operator<<(util::nostringstream& stream, const T& data)
         {
             plog::detail::operator<<(stream, static_cast<std::basic_string<util::nchar> >(data));
         }
+
+        // Print std containers
+        template<class Container>
+        inline typename meta::enableIf<!!(sizeof(typename Container::const_iterator)), void>::type operator<<(util::nostringstream& stream, const Container& data)
+        {
+            stream << "[";
+
+            for (typename Container::const_iterator it = data.begin(); it != data.end();)
+            {
+                stream << *it;
+
+                if (++it == data.end())
+                {
+                    break;
+                }
+
+                stream << ", ";
+            }
+
+            stream << "]";
+        }
 #endif
 
 #ifdef __cplusplus_cli

samples/Demo/Main.cpp

@@ -4,6 +4,14 @@
 
 #include <plog/Log.h>
 #include <plog/Initializers/RollingFileInitializer.h>
+#include <plog/Formatters/TxtFormatter.h>
+#include <plog/Appenders/ColorConsoleAppender.h>
+
+#include <vector>
+#include <deque>
+#include <list>
+#include <map>
+#include <set>
 
 #include "MyClass.h"
 #include "Customer.h"
@@ -20,7 +28,10 @@ void unmanagedFunc()
 
 int main()
 {
-    plog::init(plog::debug, "Demo.csv", 5000, 3); // Initialize the logger.
+    plog::init(plog::debug, "Demo.csv", 5000, 3); // Initialize logging to the file.
+
+    plog::ColorConsoleAppender<plog::TxtFormatter> consoleAppender;
+    plog::get()->addAppender(&consoleAppender); // Also add logging to the console.
 
     // Log macro types.
     PLOGD << "Hello log!"; // short macro
@@ -121,5 +132,50 @@ int main()
     Customer customer = { 10, "John" };
     PLOG_INFO << customer;
 
+    // Std containers can be printed
+    std::vector<int> vectorOfInts;
+    vectorOfInts.push_back(1);
+    vectorOfInts.push_back(2);
+    vectorOfInts.push_back(3);
+    PLOG_INFO << "std::vector<int>: " << vectorOfInts;
+
+    std::deque<std::string> dequeOfStrings;
+    dequeOfStrings.push_back("one");
+    dequeOfStrings.push_back("two");
+    dequeOfStrings.push_back("three");
+    PLOG_INFO << "std::deque<std::string>: " << dequeOfStrings;
+
+    std::list<const char*> listOfCharPointers;
+    listOfCharPointers.push_back("one");
+    listOfCharPointers.push_back("two");
+    listOfCharPointers.push_back(NULL);
+    PLOG_INFO << "std::list<const char*>: " << listOfCharPointers;
+
+    std::set<int> setOfInts;
+    setOfInts.insert(10);
+    setOfInts.insert(20);
+    setOfInts.insert(30);
+    PLOG_INFO << "std::set<int>: " << setOfInts;
+
+    std::map<std::string, int> mapStringToInt;
+    mapStringToInt["red"] = 1;
+    mapStringToInt["green"] = 2;
+    mapStringToInt["blue"] = 4;
+    PLOG_INFO << "std::map<std::string, int>: " << mapStringToInt;
+
+    std::multimap<int, std::string> multimapIntToString;
+    multimapIntToString.insert(std::make_pair(1, "one"));
+    multimapIntToString.insert(std::make_pair(1, "uno"));
+    multimapIntToString.insert(std::make_pair(2, "two"));
+    multimapIntToString.insert(std::make_pair(2, "due"));
+    PLOG_INFO << "std::multimap<int, std::string>: " << multimapIntToString;
+
+    std::vector<std::vector<int> > vectorOfVectorsOfInts(3);
+    vectorOfVectorsOfInts[0].push_back(1);
+    vectorOfVectorsOfInts[0].push_back(2);
+    vectorOfVectorsOfInts[1].push_back(-1);
+    vectorOfVectorsOfInts[1].push_back(-2);
+    PLOG_INFO << "std::vector<std::vector<int> >: " << vectorOfVectorsOfInts;
+
     return 0;
 }