interval-promise:带有setTimeout语义的setInterval用于promise和asyncawait

# Interval Promise [](https://npmjs.org/package/interval-promise) [](https://travis-ci.org/andyfleming/interval-promise) [](https://coveralls.io/github/andyfleming/interval-promise?branch=master) ## Overview This library provides a simple mechanism for running a promise with a given amount of time between executions. #### Standard Javascript » setInterval()  #### interval-promise » interval()  ## Installation ```bash npm install interval-promise ``` ## Usage **Simple example using async-await** ```javascript const interval = require('interval-promise') // Run a function 10 times with 1 second between each iteration interval(async () => { await someOtherPromiseReturningFunction() await another() }, 1000, {iterations: 10}) ``` ## API ```javascript interval(func, intervalLength, options = {}) // returns Promise<undefined> ``` ### Arguments <table> <thead> <tr> <th>Argument</th> <th>Attritubes</th> <th>Description</th> </tr> </thead> <tbody> <tr> <td><code><b>func</b></code></td> <td><i>function</i></td> <td><b>Required</b><br>Function to execute for each interval. <i>MUST</i> return a promise.<br><br>Two arguments are passed to this function. <ul> <li><code>iterationNumber</code> <i>number</i> — The iteration number (starting at 1)</li> <li><code>stop</code> <i>function</i> — used to "stop" (skipping all remaining iterations)</li> </ul> </td> </tr> <tr> <td><code><b>intervalLength</b></code></td> <td><i>number | function</i></td> <td><b>Required</b><br>Length in ms to wait between iterations. Should be (or return) a non-negative integer.<br><br>If a function is used, one parameter <code>iterationNumber</code> (starting at 1) is passed.</td> </tr> <tr> <td><code><b>options</b></code></td> <td><i>object</i></td> <td>Optional settings (detailed below). <tr> <td><code>options.<b>iterations</b></code></td> <td><i>number</i></td> <td><b>Default: </b><code>Infinity</code><br>The number of times to execute the function. Must be Infinity or an integer greater than 0.</td> </tr> <tr> <td><code>options.<b>stopOnError</b></code></td> <td><i>boolean</i></td> <td><b>Default: </b><code>true</code><br>If true, no subsequent calls will be made. The promise returned by interval() will be rejected and pass through the error thrown.</td> </tr> </tbody> </table> ## Project Values * **Approachability** — Basic usage should be concise and readable. * **Debuggability** — Error feedback should be helpful and error handling options should be flexible. * **Stability** — Functionality should be well-tested and reliable. ## Acknowledgements This library was inspired by [reissue](https://github.com/DonutEspresso/reissue). ## FAQ ### How can I stop the interval from _outside_ the interval function? There isn't currently direct feature to stop the iterations externally. You can, however, achieve this by checking a variable in the parent scope (of where the function is defined). Check out the code below. ```js const interval = require('interval-promise') let stoppedExternally = false const stopExternally = () => { stoppedExternally = true } interval(async (iteration, stop) => { if (stoppedExternally) { stop() } // ... normal functionality ... }, 1000) // Some other work... someOtherWork().then(() => { // Now that our "other work" is done, we can stop our interval above with: stopExternally() }) ```