> For the complete documentation index, see [llms.txt](https://structure.js.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://structure.js.org/coercion/generic-coercion.md).

# Generic coercion

If the declared type is not a primitive nor Array (or an array subclass) it'll do generic coercion. When generic coercing a value, Structure will just instantiate the declared type (using `new`) passing the raw value as the parameter (only if the raw value isn't of the declared type already).

```javascript
class Location {
  constructor({ x, y }) {
    this.x = x;
    this.y = y;
  }
}

const User = attributes({
  location: Location,
})(class User {});

const userOne = new User({
  location: new Location({ x: 1, y: 2 }),
});

userOne.location; // Location { x: 1, y: 2 } => no coercion was done

const userTwo = new User({
  location: { x: 3, y: 4 },
});

userTwo.location; // Location { x: 3, y: 4 } => coerced plain object to Location
```

Coercion to `Date` type enters in this same category, so if you have an attribute of the type `Date`, it'll use `new Date(<raw value>)` to coerce it. For more info about how this coercion works check the cases for `value` and `dateString` parameters on [Date documentation](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/Date).


---

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