README.md
# work-wrap [](https://travis-ci.org/Wain-PC/work-wrap) [](https://codeclimate.com/github/Wain-PC/work-wrap)
This tiny library makes your heavy JS code run in a separate thread in the browser.
## install
```
npm install work-wrap
or
yarn add work-wrap
```
## Usage
The code will add a single `wrap` method to the `window.Worker` object (if available). It'll fail silently when there's no `Worker` object on `window`.
## [Function] Worker.wrap(Function)
You can wrap any function as long as it's pure (**_it must not depend on any external variables_**).
```javascript
function pow(number) {
return Math.pow(number, 2);
}
var wrappedPow = Worker.wrap(pow);
wrappedPow(3).then(function (result) {
console.log(result); //9
});
```
You can pass to the wrapped function any arguments that can be serialized to JSON **and pure functions**.
Example of passing a function:
```javascript
function run(fn,number) {
return fn(number);
}
var wrappedPow = Worker.wrap(run),
passedFn = function(value) {
return Math.pow(value, 2);
}
wrappedPow(passedFn, 3).then(function (result) {
console.log(result); //9
});
```
## wrappedFn.terminate
When you run terminate the task, it will destroy the worker behind that task. If the worker was running a task, it'll **not** be finished, so make sure you terminate the worker after the work has been completed.
```javascript
task = Worker.wrap(function() {
//your heavy code here
});
//Perform your heavy task any number of times.
task();
//When you don't need your heavy task anymore, terminate the worker to free the resources and avoid memory leaks.
task.terminate();
```
## wrappedFn.restart
If you have terminated the task, the worker behind it can be restarted without wrapping the same function again. Just call `task.restart()`.
```javascript
task = Worker.wrap(function() {
//your heavy code here
});
task.terminate();
//..Some time later you need to run the task again.
task.restart();
//Run normally.
task().then(...)
```