# JS-Interpreter Async Demo

Asynchronous function calls in the real world can be wrapped to appear synchronous to code running in the JS-Interpreter. The example below (see this page's source) creates a `getXhr` function that fetches a URL and returns the content.

This function is defined using `createAsyncFunction` during initialization. When called, the interpreter is paused until the callback occurs. During this paused state, `step` and `run` will both do nothing, returning `true` to indicate that the program still has code to execute.

Click Parse, then either click Step repeatedly, or click Run once. Open your browser's console for errors.

alert(getXhr('async.txt'));

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