# Progress

Reports completed work and, when known, the total amount of work.

## Signatures

```ts
export interface Progress {
    readonly loaded: number;
    readonly total?: number | undefined;
}
```

## Why

Progress belongs to the value so loading and refreshing states can carry the same transportable measurement.

## Ownership and lifetime

This plain object acquires no resources. Its `readonly` fields are a TypeScript constraint; the runtime value is not frozen.

## Property: loaded

The finite amount of work completed so far.

## Property: loaded: Why

A required counter lets consumers render useful progress even when the total is unknown.

## Property: loaded: Ownership and lifetime

Inherits the resource-free lifetime of its enclosing `Progress` value.

## Property: total

The finite total amount of work, when the producer knows it.

## Property: total: Why

Optionality distinguishes indeterminate work from a known total without inventing a sentinel value.

## Property: total: Ownership and lifetime

Inherits the resource-free lifetime of its enclosing `Progress` value.

## Examples

```ts
import type { Progress } from "@typed/async-data"
const progress: Progress = { loaded: 4, total: 10 }
```