Creating a structured program in MQL4 involves organizing your code into logical components, leveraging functions, variables, and control structures effectively. Here’s a typical structure you might follow when developing an MQL4 program:

1. Initialization and Variable Declarations:

• Begin your code by declaring variables and initializing settings. Set global parameters such as lot sizes, stop-loss, take-profit levels, and other configurations.

2. Custom Functions:

• Define custom functions for specific tasks or calculations that you’ll reuse in your program. This step helps modularize your code and enhances readability.

3. Indicator or EA Logic:

• Implement the core logic of your indicator or expert advisor (EA) within the main function (e.g., OnInit() for indicators, OnTick() for EAs). This is where you’ll specify the rules for entering or exiting trades, analyzing market conditions, and managing positions.

4. Trade Execution and Management:

• Include functions or code blocks responsible for opening, modifying, and closing trades based on your trading strategy’s conditions. Implement risk management techniques and position sizing calculations.

5. Error Handling and Logging:

• Integrate error handling mechanisms to catch exceptions and errors that might occur during the program’s execution. Logging functionalities can be included to record important events or data for debugging purposes.

6. Optimization and Backtesting Parameters:

• Set up parameters that can be optimized during backtesting to enhance the performance of your trading strategy. These parameters might include indicators’ settings, timeframes, or entry/exit criteria.

Example Structure:

// Initialization and Variable Declarations
extern double LotSize = 0.1;
extern int StopLoss = 50;
extern int TakeProfit = 100;

// Custom Functions
double CalculateIndicatorValue() {
    // Custom calculation logic
    return value;
}

// Indicator or EA Logic
int OnInit() {
    // Initialization tasks
    return INIT_SUCCEEDED;
}

void OnTick() {
    // Main trading logic
    if (/* Condition for trade entry */) {
        // Execute trade entry
    } else if (/* Condition for trade exit */) {
        // Close open position
    }
}

// Trade Execution and Management
void OpenTrade() {
    // Code to open a trade
}

void CloseTrade() {
    // Code to close a trade
}

// Error Handling and Logging
void ErrorHandler() {
    // Handle errors
}

// Optimization and Backtesting Parameters
void SetOptimizationParameters() {
    // Set parameters for optimization
}

Tips for a Well-Structured MQL4 Program:

• Modularity: Divide your code into functions for specific tasks to improve readability and maintainability.
• Comments: Use comments to explain complex sections of your code and make it more understandable for yourself and others.
• Testing and Debugging: Perform thorough testing and debugging at each stage of development to ensure the program behaves as intended.
• Optimization and Efficiency: Optimize your code for efficiency, especially when dealing with resource-intensive operations or loops.

Adhering to a structured approach not only helps in organizing your code but also facilitates easier debugging, modification, and enhancement of your MQL4 program.