---
title: "transcode(_:from:to:stoppingOnError:into:)"
framework: swift
role: symbol
role_heading: Function
path: "swift/transcode(_:from:to:stoppingonerror:into:)"
---

# transcode(_:from:to:stoppingOnError:into:)

Translates the given input from one Unicode encoding to another by calling the given closure.

## Declaration

```swift
func transcode<Input, InputEncoding, OutputEncoding>(_ input: Input, from inputEncoding: InputEncoding.Type, to outputEncoding: OutputEncoding.Type, stoppingOnError stopOnError: Bool, into processCodeUnit: (OutputEncoding.CodeUnit) -> Void) -> Bool where Input : IteratorProtocol, InputEncoding : _UnicodeEncoding, OutputEncoding : _UnicodeEncoding, Input.Element == InputEncoding.CodeUnit
```

## Parameters

- `input`: An iterator of code units to be translated, encoded as inputEncoding. If stopOnError is false, the entire iterator will be exhausted. Otherwise, iteration will stop if an encoding error is detected.
- `inputEncoding`: The Unicode encoding of input.
- `outputEncoding`: The destination Unicode encoding.
- `stopOnError`: Pass true to stop translation when an encoding error is detected in input. Otherwise, a Unicode replacement character ("\u{FFFD}") is inserted for each detected error.
- `processCodeUnit`: A closure that processes one outputEncoding code unit at a time.

## Return Value

Return Value true if the translation detected encoding errors in input; otherwise, false.

## Discussion

Discussion The following example transcodes the UTF-8 representation of the string "Fermata 𝄐" into UTF-32. let fermata = "Fermata 𝄐" let bytes = fermata.utf8 print(Array(bytes)) // Prints "[70, 101, 114, 109, 97, 116, 97, 32, 240, 157, 132, 144]"

var codeUnits: [UTF32.CodeUnit] = [] let sink = { codeUnits.append($0) } transcode(bytes.makeIterator(), from: UTF8.self, to: UTF32.self,           stoppingOnError: false, into: sink) print(codeUnits) // Prints "[70, 101, 114, 109, 97, 116, 97, 32, 119056]" The sink closure is called with each resulting UTF-32 code unit as the function iterates over its input.