# AUR0228

## Error Message

`AUR0228: @computed decorator can only be used on a getter, "{{name}}" is not a getter.`

Where `{{name}}` is the member name the decorator was applied to.

## Description

This error occurs when `@computed` is applied to something other than a getter (for example a method, a field, or a setter). Aurelia’s `@computed` decorator only supports getter accessors.

## Example Trigger

```ts
import { computed } from '@aurelia/runtime';

export class MyVm {
  // ❌ Not a getter
  @computed
  total() {
    return 0;
  }
}
```

## Solution

Apply `@computed` to a getter.

```ts
import { computed } from '@aurelia/runtime';

export class MyVm {
  private _items: number[] = [];

  @computed
  get total() {
    return this._items.reduce((a, b) => a + b, 0);
  }
}
```

## Troubleshooting

* Confirm the decorated member is a `get ...()` accessor.
* If you need a method, remove `@computed` and call the method directly.