09. Promise Patterns

Control abstractions:

p-retry - retry async function.
p-cancellable - create a promise that can be canceled.
p-progress - create a promise that reports progress.
p-reflect - promise always fulfill with its actual fulfillment value or rejection reason.
- p-settle - same as p-reflect but for array of promises.
p-times - run async function a specific number of times concurrently.

delay - resolve promise with delay.
nanodelay - A tiny (28 bytes) Promise wrapper around setTimeout.
p-min-delay - delay a promise a minimum amount of time.
p-timeout - reject promise after a specified amount of time.
p-immediate - returns a promise resolved in the next event loop - think setImmediate().

p-map - run async functions multiple times with different inputs concurrently.
p-filter - run async functions multiple times with different inputs concurrently and get a filtered down result.
p-reduce - reduce a list of values using promises into a promise for a value.
p-all - same as Promise.all(), but accepts functions instead of promises directly so you can limit the concurrency.
p-race - fixes the silly behavior of Promise.race() returning a forever pending promise. when supplied an empty iterable, which could create some really hard to debug problems.
p-any - return the fastest promise. Use this instead of Promise.race().
p-some - use when you need the fastest of multiple promises.
p-every - like Array.every for promises.
p-one - like Array.some for promises.
p-locate - get the first fulfilled promise that satisfies the provided testing function.
p-limit - run multiple async functions with limited concurrency.
Bluebird: Promise.join - same as Promise.all(), but for fixed amount of discrete promises that you want to coordinate concurrently (more performant).

p-queue - promise queue with concurrency control.
p-series - run async functions in series.
- p-map-series - serial Promise.all with mapper function.
- p-each-series - iterate over promises serially.
p-pipe - compose async functions into a reusable pipeline.
p-waterfall - run async functions in series, each passing its result to the next.
p-props - like Promise.all() but for Map and Object.
mux - creates a promise that waits for the promises in nested data structures and resolves to data structures of the same form. It recursively traverses the input data structure and multiplexes its promises.

p-debounce - debounce async functions.
p-throttle - throttle async functions.
p-memoize - memoize promises caching the result of calls with identical input.
reuse-promise - reuse the same promise that's returned from a function until it's resolved.
p-lazy - create a lazy promise that defers execution until .then() or .catch() is called.

pify - promisify callback or CPS style functions.
p-event - promisify event (once).
p-tap - access to promise value without chaining promise.
p-log - log the value/error of a promise.
p-time - measure the time a promise takes to resolve.
Bluebird: Promise.method - wraps the given function into new function. The new function will always return a promise that is fulfilled with the original functions return values or rejected with thrown exceptions from the original function.

await-to-js - convert Promise to [err, data] outcome.
catchify - various error handling strategies for Promise.
Bluebird: filtered catch
Bluebird: .error
Bluebird: Resource management
- .disposer, objects that wrap a resource and a method to release that resource, together with.
- Promise.using, a function to safely use disposers in a way that automatically calls their release method.

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