[API reference](https://evolu.dev/docs/api-reference) › [@evolu/common](https://evolu.dev/docs/api-reference/common) › [Type](https://evolu.dev/docs/api-reference/common/Type) › MapKeyCollisionIssue

Defined in: [packages/common/src/Type.ts:9879](https://github.com/evoluhq/evolu/blob/dd96d79f1dbe9a49fa12ce8e0aa7d3d0177795ca/packages/common/src/Type.ts#L9879)

Two [map](https://evolu.dev/docs/api-reference/common/Type/functions/map) keys that decode to the same output key.

## Properties

<a id="index"></a>

### index

```ts
readonly index: number;
```

Defined in: [packages/common/src/Type.ts:9881](https://github.com/evoluhq/evolu/blob/dd96d79f1dbe9a49fa12ce8e0aa7d3d0177795ca/packages/common/src/Type.ts#L9881)

---

<a id="key"></a>

### key

```ts
readonly key: unknown;
```

Defined in: [packages/common/src/Type.ts:9882](https://github.com/evoluhq/evolu/blob/dd96d79f1dbe9a49fa12ce8e0aa7d3d0177795ca/packages/common/src/Type.ts#L9882)

---

<a id="kind"></a>

### kind

```ts
readonly kind: "Collision";
```

Defined in: [packages/common/src/Type.ts:9880](https://github.com/evoluhq/evolu/blob/dd96d79f1dbe9a49fa12ce8e0aa7d3d0177795ca/packages/common/src/Type.ts#L9880)

---

<a id="outputkey"></a>

### outputKey

```ts
readonly outputKey: unknown;
```

Defined in: [packages/common/src/Type.ts:9885](https://github.com/evoluhq/evolu/blob/dd96d79f1dbe9a49fa12ce8e0aa7d3d0177795ca/packages/common/src/Type.ts#L9885)

---

<a id="previousindex"></a>

### previousIndex

```ts
readonly previousIndex: number;
```

Defined in: [packages/common/src/Type.ts:9883](https://github.com/evoluhq/evolu/blob/dd96d79f1dbe9a49fa12ce8e0aa7d3d0177795ca/packages/common/src/Type.ts#L9883)

---

<a id="previouskey"></a>

### previousKey

```ts
readonly previousKey: unknown;
```

Defined in: [packages/common/src/Type.ts:9884](https://github.com/evoluhq/evolu/blob/dd96d79f1dbe9a49fa12ce8e0aa7d3d0177795ca/packages/common/src/Type.ts#L9884)