Object destructuring patterns

This is a TC39 proposal to add declarative pattern matching syntax to the ECMAScript language. It introduces a match expression that allows developers to inspect and branch on data structures using patterns with destructuring, guards, and logical combinators. The proposal defines a custom matcher protocol via a well-known symbol, enabling objects to implement user-defined matching logic with arbitrary extraction and decomposition. The proposal supports matching against literal primitives using SameValue equality with special handling for signed zero and NaN, as well as relational comparison

Z is a pattern matching library for JavaScript that evaluates variables against structural shapes, data types, and literal values to branch program execution conditionally. It functions as a functional programming utility designed to deconstruct arrays and objects into parts during conditional evaluation. The library transforms human-friendly pattern matching syntax into optimized nested conditional statements during compilation or initialization phases, evaluating complex structural conditions and returning matching branch results directly as standard expression values. It inspects runtime d