IIFE Patterns
IIFE (Immediately Invoked Function Expression) patterns are a JavaScript design pattern where a function is defined and executed immediately after its creation. This technique creates a private scope to avoid polluting the global namespace and can be used for module encapsulation, initialization code, or to manage variable scope. It's commonly implemented with syntax like (function() { ... })() or (() => { ... })() in modern JavaScript.
Developers should learn IIFE patterns when writing JavaScript code that needs to isolate variables and functions from the global scope, especially in legacy codebases or when creating self-contained modules without modern module systems. They are useful for avoiding naming conflicts, implementing the module pattern before ES6 modules, and executing initialization logic immediately on script load, such as in library bootstrapping or configuration setup.