---
title: "registerCoercer(_:selector:toConvertFrom:to:)"
framework: foundation
role: symbol
role_heading: Instance Method
path: "foundation/nsscriptcoercionhandler/registercoercer(_:selector:toconvertfrom:to:)"
---

# registerCoercer(_:selector:toConvertFrom:to:)

Registers a given object (typically a class) to handle coercions (conversions) from one given class to another.

## Declaration

```swift
func registerCoercer(_ coercer: Any, selector: Selector, toConvertFrom fromClass: AnyClass, to toClass: AnyClass)
```

## Parameters

- `coercer`: The object that performs the coercion. coercer should typically be a class object.
- `selector`: A selector that specifies the method to perform the coercion. selector should typically be a factory method, and must take two arguments. The first is the value to be converted. The second is the class to convert it to.
- `fromClass`: The class for which instances are coerced.
- `toClass`: The class to which instances of fromClass are coerced.

## See Also

### Working with handlers

- [coerceValue(_:to:)](foundation/nsscriptcoercionhandler/coercevalue(_:to:).md)