Understanding Exception Handling in Elixir

The content provided is a detailed guide on how to handle exceptions in Elixir, written by Pulkit Goyal. It starts by introducing the concept of exceptions, a means to signal errors or crashes in a program. Elixir, being built on the Erlang VM, follows the philosophy of 'let it crash', which advocates for allowing processes to end on failure and leveraging OTP primitives for process supervision and restart. The article provides examples of raising exceptions in Elixir, demonstrating the use of 'ArithmeticError' through an attempted division by zero and showcasing manual exception raising using 'raise'. Furthermore, it discusses the use of the 'raise/2' function for raising custom exceptions within a module, followed by examples of handling exceptions using the 'try' and 'rescue' constructs. The article explains the benefits of specific exception handling over a generic approach, advocating for clarity and maintainability. It also introduces the Elixir community's common practice of using 'ok/error' tuples for error signaling over raising exceptions. In addition to 'try' and 'rescue', the article elaborates on 'reraise' for preserving exception stack traces, the distinction between 'rescue' and 'catch', usage of 'after' and 'else' blocks, and the implications of exceptions on Elixir processes. The author encourages monitoring exceptions to address developer errors and crashes, introducing AppSignal as a tool for this task. The article concludes with best practices for library authors and general advice on exception handling, emphasizing the appropriate use of exceptions and process crashes in Elixir applications.