fastest_use_ostr_like.cpp

This usage:

• Fastest. It does not use formatters and destinations (thus, the flexibility that comes with formatters/destinations) is gone
• You have one filter, which can be turned on or off
• You have 2 loggers: app and err.
• The app writes to console, the err writes to "err.txt" file
• It uses the << operator as the logging syntax

Here's what the output will be:

The console:

this is so cool 1
this is so cool again 2
hello, world
good to be back ;) 4

The err.txt file:

first error 3
second error 5

#define BOOST_LOG_COMPILE_FAST_OFF
#include <boost/logging/logging.hpp>
#include <boost/logging/format.hpp>

using namespace boost::logging;

typedef logger< default_, destination::cout> app_log_type;
typedef logger< default_, destination::file> err_log_type;

BOOST_DEFINE_LOG_FILTER(g_log_filter, filter::no_ts )

BOOST_DEFINE_LOG(g_log_app, app_log_type )
BOOST_DEFINE_LOG_WITH_ARGS( g_log_err, err_log_type, ("err.txt") )

#define LAPP_ BOOST_LOG_USE_LOG_IF_FILTER(g_log_app(), g_log_filter()->is_enabled() ) 
#define LERR_ BOOST_LOG_USE_LOG_IF_FILTER(g_log_err(), g_log_filter()->is_enabled() ) 

void fastest_use_ostr_like_example() {
    g_log_app()->mark_as_initialized();
    g_log_err()->mark_as_initialized();

    int i = 1;
    LAPP_ << "this is so cool " << i++ << "\n";
    LAPP_ << "this is so cool again " << i++ << "\n";
    LERR_ << "first error " << i++ << "\n";

    std::string hello = "hello", world = "world";
    LAPP_ << hello << ", " << world << "\n";

    g_log_filter()->set_enabled(false);
    LAPP_ << "this will not be written to the log";
    LAPP_ << "this won't be written to the log";
    LERR_ << "this error is not logged " << i++;

    g_log_filter()->set_enabled(true);
    LAPP_ << "good to be back ;) " << i++ << "\n";
    LERR_ << "second error " << i++ << "\n";
}




int main() {
    fastest_use_ostr_like_example();
}


// End of file

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Copyright John Torjo © 2007
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