# noretry

A simple retry library for Rust with both sync and async support.

## Usage

Async (enabled by default via the `tokio` feature):

```rust
let result = noretry::retry_async(|| async {
    do_something().await
})
.await
.map_err(|e| e.into_inner())?;
```

Sync:

```rust
let result = noretry::retry(|| {
    do_something()
})
.map_err(|e| e.into_inner())?;
```

Both use sensible defaults: 3 attempts, exponential backoff, 100ms initial delay, 30s cap, and jitter.

Errors returned from the closure are automatically treated as transient (retryable) via the `From` impl on `Retryable`. Use `?` as normal and retries happen transparently.

## Features

The `tokio` feature is enabled by default, providing `retry_async` and `run_async`. To use only the sync API:

```toml
noretry = { version = "0.1", default-features = false }
```

## Builder

For more control, use the builder with `run` (sync) or `run_async`:

```rust
noretry::builder()
    .with_max_attempts(5)
    .with_linear_backoff()
    .build()
    .run_async(|| async {
        do_something().await
    })
    .await?;
```

## Backoff strategies

Exponential backoff (default):

```rust
noretry::builder()
    .with_exponential_backoff()
    .build()
```

Linear backoff:

```rust
noretry::builder()
    .with_linear_backoff()
    .build()
```

Both strategies support configurable initial delay, max delay cap, and jitter (enabled by default):

```rust
use std::time::Duration;

noretry::builder()
    .with_initial_delay(Duration::from_millis(200))
    .with_max_delay(Duration::from_secs(10))
    .with_jitter(false)
    .build()
```

## Permanent errors

If an error should not be retried, mark it as permanent using `map_err`:

```rust
use noretry::Retryable;

noretry::builder()
    .build()
    .run_async(|| async {
        do_something()
            .await
            .map_err(Retryable::permanent)?
    })
    .await;
```

The result is a `RetryError::Permanent` or `RetryError::Exhausted`, both of which carry the original error. Call `.into_inner()` to extract it.
