When it comes to debugging Hack code, there are several techniques and tools available to assist in identifying and fixing issues. Here are some common ways to debug Hack code:

1. Print Statements : Adding print statements at strategic points in your code can help you observe the values of variables and the flow of execution. This is a simple and effective method for understanding the program's behavior and identifying potential issues.

2. Debuggers : Hack supports debugging with the help of debuggers integrated with development environments or standalone tools. Debuggers allow you to set breakpoints at specific lines or functions in your code, step through the execution, inspect variables, and analyze the program's state. Xdebug is a popular debugger used with Hack.

3. Logging : Incorporating logging statements throughout your code can provide valuable information during debugging. Use logging libraries or built-in logging functions to capture relevant data, such as variable values, function calls, and error messages. You can then review the log output to understand the program's flow and identify problematic areas.

4. Error Handling and Exception Handling : Proper error handling and exception handling techniques can help you identify and manage errors in your Hack code. By implementing try-catch blocks and error handling mechanisms, you can catch and handle exceptions, log error messages, and gather diagnostic information for debugging purposes. 5. Interactive Debugging in IDEs : Integrated Development Environments (IDEs) that support Hack often provide interactive debugging capabilities. These features allow you to set breakpoints, step through code, inspect variables, and view the program's execution state in real-time. IDEs such as Visual Studio Code with the Hack plugin offer debugging support for Hack code.

6. Unit Testing and Test-Driven Development : Writing comprehensive unit tests can aid in the debugging process by allowing you to isolate and identify issues in specific parts of your code. Test-driven development (TDD) practices encourage writing tests before implementing code, ensuring that you have a mechanism to verify your code's behavior and quickly identify regressions.

7. Static Code Analysis Tools : Utilize static code analysis tools that can analyze your Hack code for potential issues, including security vulnerabilities, code smells, and potential bugs. These tools can provide insights into potential problems in your codebase, helping you identify areas that require further investigation.

8. Code Reviews and Pair Programming : Collaborating with colleagues through code reviews and pair programming sessions can help catch bugs and identify issues that may not be immediately apparent to the original developer. Multiple perspectives can improve code quality and reduce the time spent on debugging.

By combining these approaches, you can effectively debug Hack code and resolve issues more efficiently. Choose the methods that suit your development environment, workflow, and specific debugging needs.