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Error Description
Info
The Error Description is a Library for MetaTrader 5 that the library contains the following functions:tradeserverreturncodedescription -returns description of trade server return codes;errordescription - returns description of runtime errors. //+------------------------------------------------------------------+ //| ErrorDescription.
Usage
This tool is typically used for enhancing chart analysis and decision making.
Platform
This Library works exclusively on MetaTrader 5 (both build 600+ and newer versions).
Setup
Place the downloaded file in MQL5/Libraries folder via File ? Open Data Folder in MetaTrader 5.
How to Install and Use Error Description
1. Storage: Place library files in the MQL/Libraries directory to ensure they are accessible to your projects.
2. Implementation: Include the library in your code using the #import directive, ensuring you match the exact function names and parameters.
3. Compilation: Ensure the library is present in the directory before you compile your main EA or script, as the compiler links them during this phase.
4. Management: Keep libraries organized in sub-folders if you manage many custom functions to maintain a clean project structure.
Frequently Asked Questions
Q: What is a library file used for? A: Libraries store reusable code modules, allowing you to centralize common logic used by multiple EAs or indicators.
Q: Is a library executable? A: No, libraries are non-executable files containing functions; they must be imported into an EA, indicator, or script to function.
Q: Can I update a library while the platform is running? A: You should compile your EA or script after updating a library to ensure the latest code changes are integrated.
What this tool does
The library contains the following functions:TradeServerReturnCodeDescription -returns description of trade server return codes;ErrorDescription - returns description of runtime errors.
Typical Use Case
This Library excels in automated trading and technical analysis on MetaTrader 5.
Compatible Platform & Setup
This Library works on MetaTrader 5. Place the file in the MQL5/Libraries folder and restart the terminal.
Description & Settings
Related: Result Retcode Description - another powerful library for MetaTrader 5 traders.
The library contains the following functions:
TradeServerReturnCodeDescription -
returns description of trade server return codes;
Also recommended: Error Desc - similar library with strong performance on MetaTrader 5.
ErrorDescription -
returns description of runtime errors.//+------------------------------------------------------------------+ //| ErrorDescription.mqh | //| Copyright 2010, MetaQuotes Software Corp. | //| | //+------------------------------------------------------------------+ #property copyright "2010, MetaQuotes Software Corp." #property link " #property version "1.00" //+------------------------------------------------------------------+ //| returns trade server return code description | //+------------------------------------------------------------------+ string TradeServerReturnCodeDescription(int return_code) //+------------------------------------------------------------------+ //| returns runtime error code description | //+------------------------------------------------------------------+ string ErrorDescription(int err_code)
Example:
(Don't forget to copy the file
ErrorDescription.mq5
to the folder \MetaTrader 5\MQL5\Include)
//+------------------------------------------------------------------+ //| ErrorDescrTest.mq5 | //| Copyright 2010, MetaQuotes Software Corp. | //| | //+------------------------------------------------------------------+ #property copyright "2010, MetaQuotes Software Corp." #property link " #property version "1.00" #include <ErrorDescription.mqh> //+------------------------------------------------------------------+ //| Example of use of the ErrorDescription.mqh library | //+------------------------------------------------------------------+ void OnStart() { Print("----- Description of trade server return codes -----"); for(int i=10004;i<=10034;i++) { Print("Trade server return code:",i,TradeServerReturnCodeDescription(i)); } Print("-------- Description of runtime error codes ---------"); for(int i=4001;i<=4014;i++) { Print("Runtime error code:",i,ErrorDescription(i)); } } //+------------------------------------------------------------------+
In some cases it's necessary to work with user defined errors. In MQL5 there is a function SetUserError, what sets the predefined variable _LastError into the value equal to ERR_USER_ERROR_FIRST + user_error.
The user defined error codes starts from code ERR_USER_ERROR_FIRST. In such cases you can use the function
ErrorDescriptionExt
to return description of errors, including the user defined errors:
//+------------------------------------------------------------------+ //| UserErrorDescr.mq5 | //| Copyright 2010, MetaQuotes Software Corp. | //| | //+------------------------------------------------------------------+ #property copyright "2010, MetaQuotes Software Corp." #property link " #property version "1.00" #include <ErrorDescription.mqh> //+------------------------------------------------------------------+ //| returns runtime error code description, | //| with user defined errors | //+------------------------------------------------------------------+ string ErrorDescriptionExt(int err_code,string&user_errors[]) { if(err_code>=0 && err_code<ERR_USER_ERROR_FIRST) return(ErrorDescription(err_code)); //--- user defined runtime errors err_code-=ERR_USER_ERROR_FIRST; if(err_code<=ArraySize(user_errors)) return(user_errors[err_code]); //--- return("Unknown error"); }; // an array with description of the user defined runtime errors string MyErrors[]= { "User error №1", "User error №2", "User error №3" }; //+------------------------------------------------------------------+ //| Script program start function | //+------------------------------------------------------------------+ void OnStart() { //--- for(int i=0;i<=2;i++) { SetUserError(i); Print("User defined error code:",i,ErrorDescriptionExt(GetLastError(),MyErrors)); } } //+------------------------------------------------------------------+
You may also like: MQ L Plus Enhanced Error Handler Support - excellent alternative for library users on MetaTrader 5.
⚠ Limitations & Risk Warning
- This tool is provided for educational and testing purposes only.
- Past performance does not guarantee future results.
- Trading involves substantial risk of loss. Use on a demo account first.
- Results may vary depending on market conditions, broker, and settings.
- We recommend thorough backtesting and forward testing before using with real funds.