RxJS Reactive Programming Patterns

Quick Guide: RxJS composes async work as streams. Observables are lazy — nothing runs until subscribe() — and operators inside pipe() describe a pipeline rather than execute one. Three decisions carry most of the weight: which flattening operator (switchMap cancels, mergeMap parallelises, concatMap queues, exhaustMap ignores), where catchError sits (inside the inner pipe, or an error kills the outer stream permanently), and how the subscription ends. Suffix observable variables with $.

Detailed Resources:

• examples/core.md — creation, lazy execution with defer, transformation, error recovery, Promise interop
• examples/higher-order.md — switchMap, mergeMap, concatMap, exhaustMap worked through
• examples/subjects.md — the four Subject types, multicasting, shareReplay
• examples/combination.md — combineLatest, forkJoin, merge, concat, race
• examples/memory-leaks.md — the takeUntil pattern, subscription collections, self-completing streams
• reference.md — operator tables, scenario-to-operator lookup, deprecations