# Sink.Success

Extracts the successful input type consumed by a `Sink`.

## Signatures

```ts
type Success<T> = T extends Sink<infer _A, infer _E, infer _R> ? _A : never;
```

## Why

Library code can derive a consumer's input without repeating its generic arguments.

## Ownership and lifetime

This conditional type is compile-time only and acquires no resources.