Refactored logging interface.

src/anthem/Translation.cpp

@@ -35,8 +35,7 @@ void translate(const std::vector<std::string> &fileNames, Context &context)
 
 void translate(const char *fileName, std::istream &stream, Context &context)
 {
-	// TODO: refactor
-	context.logger.log(output::Priority::Info, (std::string("reading ") + fileName).c_str());
+	context.logger.log(output::Priority::Info) << "reading " << fileName;
 
 	auto fileContent = std::string(std::istreambuf_iterator<char>(stream), {});
 
@@ -51,7 +50,7 @@ void translate(const char *fileName, std::istream &stream, Context &context)
 	const auto logger =
 		[&context](const Clingo::WarningCode, const char *text)
 		{
-			context.logger.log(output::Priority::Error, text);
+			context.logger.log(output::Priority::Error) << text;
 		};
 
 	Clingo::parse_program(fileContent.c_str(), translateStatement, logger);

src/anthem/output/Logger.cpp

@@ -1,6 +1,7 @@
 #include <anthem/output/Logger.h>
 
 #include <anthem/output/Formatting.h>
+#include <anthem/output/NullStream.h>
 
 namespace anthem
 {
@@ -92,28 +93,29 @@ void Logger::setColorPolicy(ColorStream::ColorPolicy colorPolicy)
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 
-void Logger::log(Priority priority, const char *message)
+FormatScope Logger::log(Priority priority)
 {
 	const auto priorityID = static_cast<int>(priority);
 
 	if (priorityID < static_cast<int>(m_logPriority))
-		return;
+		return FormatScope(detail::nullStream);
 
 	m_errorStream
 		<< priorityFormat(priority) << priorityName(priority) << ":"
 		<< ResetFormat() << " "
-		<< MessageBodyFormat << message
-		<< ResetFormat() << std::endl;
+		<< MessageBodyFormat;
+
+	return FormatScope(m_errorStream);
 }
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 
-void Logger::log(Priority priority, const input::Location &location, const char *message)
+FormatScope Logger::log(Priority priority, const input::Location &location)
 {
 	const auto priorityID = static_cast<int>(priority);
 
 	if (priorityID < static_cast<int>(m_logPriority))
-		return;
+		return FormatScope(detail::nullStream);
 
 	m_errorStream
 		<< LocationFormat
@@ -121,8 +123,9 @@ void Logger::log(Priority priority, const input::Location &location, const char
 		<< ResetFormat() << " "
 		<< priorityFormat(priority) << priorityName(priority) << ":"
 		<< ResetFormat() << " "
-		<< MessageBodyFormat << message
-		<< ResetFormat() << std::endl;
+		<< MessageBodyFormat;
+
+	return FormatScope(m_errorStream);
 }
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////

src/anthem/output/NullStream.cpp

@@ -0,0 +1,24 @@
+#include <anthem/output/NullStream.h>
+
+namespace anthem
+{
+namespace output
+{
+namespace detail
+{
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+//
+// NullStream
+//
+////////////////////////////////////////////////////////////////////////////////////////////////////
+
+NullBuffer nullBuffer;
+std::ostream nullOStream(&nullBuffer);
+ColorStream nullStream(nullOStream);
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+
+}
+}
+}