MQL Plus Enhanced Error Handler Support - library for MetaTrader 5

Current Version 1.00

Encapsulates error code and text handling.

Supported features:

• User defined error codes
• Error code groups
• Customizable output string
• Seemless integration

Error code handling and error code resolving to text messages is a pain. This include file will solve some of the daily issues of handling error codes.

Example code:

//*********************************************************************************************************************************************************/
// Return codes
//


///////////////////////////////////////
//
// Define error group id 
//  This ID must be unique within
//  the given project.
//
//  Valid values for Group ID are
//  between 0x00 and 0xEF
//  0xF0 to 0xFF is reserved.
//
//  Error codes categories
//      0x00            = Succes 
//      0x01 ... 0xDF   = Errors, 
//      0xE0 ... 0xEF   = Warnings
//      0xF0 ... 0xFF   = Handled Errors
//
#define EA_ERRGROUP_CODE_SIG_GENERATOR      0x01

// Define internal set codes
#define _SIG_SUCCESS                        LIB_ERROR_CODE(EA_ERRGROUP_CODE_SIG_GENERATOR, 0x00)
#define _SIG_ERR_INVALID_VALUE              LIB_ERROR_CODE(EA_ERRGROUP_CODE_SIG_GENERATOR, 0x01)
#define _SIG_ERR_CREATE_SIGNAL              LIB_ERROR_CODE(EA_ERRGROUP_CODE_SIG_GENERATOR, 0x02)
#define _SIG_ERR_INVALID_SYMBOL             LIB_ERROR_CODE(EA_ERRGROUP_CODE_SIG_GENERATOR, 0x03)
#define _SIG_ERR_INDICATOR                  LIB_ERROR_CODE(EA_ERRGROUP_CODE_SIG_GENERATOR, 0x04)

// Define global return codes
#define SIG_SUCCESS                         LIB_ERROR_CODE_EXPORT(_SIG_SUCCESS)
#define SIG_ERR_INVALID_VALUE               LIB_ERROR_CODE_EXPORT(_SIG_ERR_INVALID_VALUE)
#define SIG_ERR_CREATE_SIGNAL               LIB_ERROR_CODE_EXPORT(_SIG_ERR_CREATE_SIGNAL)
#define SIG_ERR_INVALID_SYMBOL              LIB_ERROR_CODE_EXPORT(_SIG_ERR_INVALID_SYMBOL)
#define SIG_ERR_INDICATOR                   LIB_ERROR_CODE_EXPORT(_SIG_ERR_INDICATOR)

// Define message resolver
LIB_ERR_REGISTER_RESOLVER_BEGIN(EA_ERRGROUP_CODE_SIG_GENERATOR)
    LIB_ERR_REGISTER_RESOLVER_MSGCODE(SIG_SUCCESS,              "Operation success. All values could be calculated within given parameters.")
    LIB_ERR_REGISTER_RESOLVER_MSGCODE(SIG_ERR_INVALID_VALUE,    "Operation aborted. Invalid function input.")
    LIB_ERR_REGISTER_RESOLVER_MSGCODE(SIG_ERR_CREATE_SIGNAL,    "Operation failed. Unable to create signal.")
    LIB_ERR_REGISTER_RESOLVER_MSGCODE(SIG_ERR_INVALID_SYMBOL,   "Operation failed. Invalid symbol specified.")
    LIB_ERR_REGISTER_RESOLVER_MSGCODE(SIG_ERR_INDICATOR,        "Operation failed. Indicator could not be created.")
LIB_ERR_REGISTER_RESOLVER_END(EA_ERRGROUP_CODE_SIG_GENERATOR)


//
// END Return codes
//*********************************************************************************************************************************************************/




bool CalcInit()
{
    // Ichimoku Kinju Sen

        // Create baseline indicator
        hBL = iIchimoku(fw_cfg::CustomSymbol, fw_cfg::CustomTimeframe, 9, BasePeriods, 52);

        if(hBL == INVALID_HANDLE)
        {
            // Set the internal error code (Using underscore to distinguish between set and retrieve error code)
            err_SetUserError(_SIG_ERR_INDICATOR, "symbol = " + fw_cfg::CustomSymbol);   
            return(false);
        }

        // Configure baseline buffer
        nBLbuffer = 1;

    // Return
    return(true);
}



void do_calc()
{
    // User defined error codes
    if(!CalcInit())
    {
        string error_msg = err_ResolveLastError();

        // ... OR ...

        printf(err_ResolveLastError());
    }

    // MQL error codes
    if(CopyBuffer() == -1)
    {
        string error_msg = err_ResolveLastError();

        // ... OR ...  // See doc for options on calling this function

        printf(err_ResolveLastError());
    }

    // Return
    return;
}