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proxy.golang.org : github.com/asmsh/promise

Package promise provides fast, lightweight, and lock-free promise implementations. Besides speed and low memory overhead, it focuses on Go's idioms, like multi return parameters, error being a value, the convention of returning errors as the last return parameter, and the existence of panics and their difference from errors. A Promise provides an easy way for returning results from a goroutine, and/or waiting for it to finish, plus other features. States and Fates:- A Promise has four states, and it can be in only one of them, at any time: * Pending: the computation that corresponds to this Promise has not finished. * Fulfilled: the computation that corresponds to this Promise has finished and returned a Res value with no error or with a nil error at the end. * Rejected: the computation that corresponds to this Promise has finished and returned a Res value with a non-nil error at the end. * Panicked: the computation that corresponds to this Promise has caused a panic. A Promise has three fates, and it can be in only one of them, at any time: * Unresolved: the computation that corresponds to this Promise is still working, and the final state of the Promise is still unknown. * Resolved: the state of the Promise is now known, and final. * Handled: the result of the Promise has been passed to some call of its methods. General Notes:- * Once the Promise's fate is Resolved, its result value will not change. * A Promise whose fate is Unresolved, its state must be Pending. * A Promise whose fate is Resolved, and its state is Pending, its fate will never be Handled. * For a Promise's fate to be Handled, its fate must first be Resolved. Implementations:- * The module provides one Promise implementation, GoPromise(the default). * The GoPromise's 'ok' callback parameter will always be true(except in a Finally callback on a panicked promise). * The GoPromise's 'ok' return parameter(for GetRes) will always be true( except on a panicked promise). Callback Notes:- * The Res value returned from the callback must not be modified after return. * If the callback called runtime.Goexit, the returned promise will be fulfilled to 'nil'. * The underlying implementation of the returned Promise is always the default implementation(GoPromise), unless stated otherwise in the callback or the corresponding constructor docs. * If the callback returned a non-nil error value as the last element in the returned Res value, the returned Promise will be a 'rejected' promise, and all subsequent promises in any promise chain derived from it, until the error is caught on each of these chains(by a Catch call). * If the promise is running in the safe mode(the default), the returned Promise is a rejected promise, and the error is not caught(by a Catch call) before the end of that promise's chain, or the promise result is not read(by a GetRes call), a panic will happen with an error value of type *UnCaughtErr, which has that uncaught error 'wrapped' inside it. * If the callback caused a panic, the resulting Promise will be a 'panicked' promise, and all subsequent promises in any promise chain derived from it, until recovering from the panic on each of these chains(by a Recover call). * If the promise is running in the safe mode(the default), the returned Promise is a panicked promise, and it's not recovered(by a Recover call) before the end of the promise's chain, or before calling Finally, it will re-panic(with the same value passed to the original 'panic' call). Modes:- * The module provides two modes for promise creation, 'Safe', and 'NonSafe'. * In the 'NonSafe' version, a 'rejected' or 'panicked' promise(resolved to the 'rejected' state or the 'panicked' state, respectively) will not panic if it reached the end of its promise chain without being handled( by a 'Catch' call or 'GetRes' call, in case of a 'rejected' promise, or a 'Recover' call, in case of 'panicked' promise). But in the 'Safe' version a panic will happen in either of these cases. * The 'NonSafe' version is accessible from the NonSafeAPI variable. * The 'Safe' version is the default, and is accessible from any function in the module.

Registry - Source - Documentation - JSON
purl: pkg:golang/github.com/asmsh/promise
Keywords: async, asynchronous, futures, go, golang, goroutine, library, pipeline, promise, promises
License: Apache-2.0
Latest release: over 2 years ago
First release: over 3 years ago
Namespace: github.com/asmsh
Stars: 0 on GitHub
Forks: 0 on GitHub
See more repository details: repos.ecosyste.ms
Last synced: 20 days ago

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