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Closing Channels

To close a channel, call the .close() method on it.

While receiving data from a closed channel is fine, sending data on a closed channel will cause an error to be thrown.

For that reason, it’s best practice that the function that sends messages on the channel, will be the one that closes it.

If the channel is closed and there are no more messages in the buffer, calling .get() will resolve immediately with [undefined, false]. On all other cases it will resolve (when a value is available) with [THE_VALUE, true].

Note: Channel.from(...) and the built-in pipe functions will close the channel when they are done consuming the input. If the input was another Channel, then you have to close the input channel, for that to happen.


import { Channel } from "...";
const input = new Channel();
const p = input.forEach((x) => console.log(".forEach() got: ", x))
  .finally(() => console.log(".forEach() was resolved"));

await input.send("Hello"); // => .forEach() got: Hello
await input.send("world"); // => .forEach() got: world
console.log(await p);
// => .forEach() was resolved
// => [undefined, false]

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