What is railway oriented programming?

Railway Oriented Programming (ROP) is a functional programming approach that uses a metaphor of railway tracks to handle errors and control flow in a codebase, ensuring each function or method returns either a success or a failure. This pattern emphasizes the separation of the "happy path," where operations succeed smoothly, from the "unhappy path," where errors occur and are managed through exceptions. It enhances code readability and maintainability by using monadic behavior to manage errors, providing a structured way to deal with potential issues like invalid inputs or missing data. By allowing functions to switch tracks based on success or failure, ROP offers a clear, efficient, and reliable method for error handling and flow control, which can be beneficial in real-world applications that require robustness and clarity. The technique is not a strict rule but a design choice that developers can adopt to improve the efficiency and reliability of their code, offering advantages such as authenticity, clarity, and compatibility without impacting performance.