share

Turns a cold Observable into a hot, multi-subscribable one.

Signature

share(config?: ShareConfig): MonoTypeOperatorFunction

What it does

Under the hood: a Subject + refCount. The first subscriber triggers the subscription to the source; later subscribers get the same stream without restarting the source. When the subscriber count hits zero, it unsubscribes from the source. The config object lets you tune what happens on reset/error/complete.

When to use

One HTTP request for several components, a shared event stream (a WebSocket, for example), any heavy computation you don't want to repeat per subscriber.

See also

shareReplay, multicast, Subject