---
title: "superDecoder(forKey:)"
framework: swift
role: symbol
role_heading: Instance Method
path: "swift/keyeddecodingcontainerprotocol/superdecoder(forkey:)"
---

# superDecoder(forKey:)

Returns a Decoder instance for decoding super from the container associated with the given key.

## Declaration

```swift
func superDecoder(forKey key: Self.Key) throws -> any Decoder
```

## Parameters

- `key`: The key to decode super for.

## Return Value

Return Value A new Decoder to pass to super.init(from:).

## Discussion

Discussion note: DecodingError.keyNotFound if self does not have an entry for the given key. note: DecodingError.valueNotFound if self has a null entry for the given key.