# runIt

***runIt(function(){** // do something here with this **})***

* **The context object** is available as a receiver (*this*).
* **The return value** is the lambda result.

*runIt* does the same as *withIt* but it is implemented as an extension function. So like *letIt*, you can call it on the context object using dot notation.

*runIt* is useful when your lambda function both initializes objects and computes the return value.

```ts
const service = new MultiportService("https://api.example.com/data", 80)

const result = service.runIt(function () {
    this.port = 8080;
    const result = this.query(prepareRequest());
    console.debug(`Request sent to port ${this.port}"`);
    return result;
});

// the same code written with letIt() function:
const letResult = service.letIt(it => {
    it.port = 8080;
    const result = it.query(prepareRequest());
    console.debug(`Request sent to port ${it.port}"`);
    return result;
});
```

You can also invoke *runIt* as a non-extension function. The non-extension variant of *runIt* has no context object, but it still returns the lambda result. Non-extension run lets you execute a block of several statements where an expression is required. In code, non-extension *runIt* can be read as "**run the code block and compute the result.**"

```ts
const hexNumberRegex = runIt(() => {
    const digits = "0-9"
    const hexDigits = "A-Fa-f"
    const sign = "+-"

   return  new RegExp(`[${sign}]?[${digits}${hexDigits}]+`, "g");
});

let match;
while ((match = hexNumberRegex.exec("+123 -FFFF !%*& 88 XYZ")) !== null) {
    console.log(match[0]);
}
```