This is object-oriented method chaining. Not the same thing as functional composition (piping is essentially just left-to-right composition), which is what's me

This is object-oriented method chaining. Not the same thing as functional composition (piping is essentially just left-to-right composition), which is what's mentioned in the OP. It's also nowhere near as flexible, because it requires the return value to be responsible for providing a set of APIs for the next method call on every step of the chain, whereas each function in a functional composition can operate on any arbitrary input/output. There's actually a proposal for a pipeline operator in JS that I personally really like: https://github.com/tc39/proposal-pipeline-operator https://github.com/tc39/proposal-pipeline-operator I have no idea if it's getting enough traction to get standardized anytime soon though. In lieu of that, I personally just use Ramda's `pipe` function: http://ramdajs.com/docs/#pipe http://ramdajs.com/docs/#pipe Which accomplishes the same thing, but with a bit more ceremony, and not quite as convenient in a scripting setting.