# Fx.map

Transforms the elements of an Fx using a provided function.

## Signatures

```ts
export declare const map: {
    <A, B>(f: (a: A) => B): <E, R>(self: Fx<A, E, R>) => Fx<B, E, R>;
    <A, E, R, B>(self: Fx<A, E, R>, f: (a: A) => B): Fx<B, E, R>;
};
```

## Why

`map` changes each pushed value without changing when values arrive. It emits exactly once for
every upstream success, in upstream order; the callback is synchronous and cannot add failures
or services.

## Ownership and lifetime

This operation acquires no resources and retains no state. Running the result runs the source in
the same Scope, and interruption or failure is forwarded unchanged.

## Examples

```ts
import { Fx } from "@typed/fx"

const labels = Fx.fromIterable([1, 2, 3]).pipe(Fx.map((n) => `item-${n}`))
```