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MetaTrader 4 Libraries | Logging library for mql4

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This is a logging library to quickly add logging capabilities to your code without  much hassle. The library's default behavior matches most cases however most of the functionality can be customized using pre-processor substitutions (#define)

See the example scripts on how to use library.

How to use

#include <Logger.mqh>    //+------------------------------------------------------------------+  //| Script program start function                                    |  //+------------------------------------------------------------------+  void OnStart()    {     DEBUG("This id debug");     INFO("This is info");     ERROR("This is an error");    }  //+------------------------------------------------------------------+

Customization notes

    • The logger uses following format to print logs
      // [time, except LOGGER_PRINT,LOGGER_ALERT] [level] [prefix] [message] [last error, only Logger::Error]
      sample output: 2021.06.08 17:35:34 | Error | OnStart | This is a test error | invalid function parameter value
        • Use following logging functions/digits to assign them to logging levels. define as 0 if the level needs to be disabled
          #define LOGGER_PRINT    1     // print to log  #define LOGGER_ALERT    2     // trigger alert  #define LOGGER_FILE     4     // write to a file  #define LOGGER_NOTIFY   8     // send a notification

          example:

          #define LOGGER_SET_DEBUG 0       // DEBUG is disabled  #define LOGGER_SET_INFO  1|2     // Print and alert  #define LOGGER_SET_ERROR 1|2|4   // Print, alert and file write 
          • Customize the prefix section as follows
          #define LOGGER_PREFIX __FILE__ + " | Line:" + IntegerToString(__LINE__) // [filename] | [Line number]
          an example prefix output will be : with_customization.mq4 | Line:36
          • Customize file name by a string constant or a function call
          #define LOGGER_FILENAME "backtest_debug.log"  // or  #define LOGGER_FILENAME IntegerToString(AccountNumber())

          Notes:

          • #define before the Logger.mqh is included.
          • To disable a logger level set the level as zero.
          • LOGGER_NOTIFY and LOGGER_FILE execution errors are handled as a print statements. Do not customize it to use library's own error handling, the program might trigger an infinite loop or a stack overflow.
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