Issues with Typescript

Attempting to use `bind` throws this compilation error:

```
TS1241: Unable to resolve signature of method decorator when called as an expression.
Type 'TypedPropertyDescriptor' is not assignable to type 'void | TypedPropertyDescriptor<(userInfo: Readonly) => void>'.
Type 'TypedPropertyDescriptor' is not assignable to type 'TypedPropertyDescriptor<(userInfo: Readonly) => void>'.
Types of property 'value' are incompatible.
Type 'unknown' is not assignable to type '((userInfo: Readonly) => void) | undefined'.
Type 'unknown' is not assignable to type '(userInfo: Readonly) => void'.
```

No source file, test, TypeScript version, or reproduction project is mentioned. Start by reproducing the reported compilation error with the bind decorator, then inspect the bind decorator's TypeScript typing; done means the reported error no longer occurs without breaking the decorator's existing behavior.

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