# Rustic Result

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Result monad for Elixir inspired by Rust
[Result](https://doc.rust-lang.org/std/result/) type.

## Installation

This package can be installed by adding `rustic_result` to your list of
dependencies in `mix.exs`:

```elixir
def deps do
  [
    {:rustic_result, "~> 0.1.0"}
  ]
end
```

## Usage

```elixir
import Rustic.Result

ok(42)
# {:ok, 42}

err(:not_found)
# {:error, :not_found}

ok(1) |> and_then(fn v -> ok(v + 1) end)
# ok(2)

ok(1) |> and_then(fn _ -> err(:not_found) end)
# err(:not_found)

err(:not_found) |> and_then(fn v -> ok(v + 1) end)
# err(:not_found)

ok(1) |> or_else(fn _ -> ok(2) end)
# ok(2)

err(:not_found) |> or_else(fn :not_found -> ok(1) end)
# ok(1)

err(:not_found) |> or_else(fn :not_found -> err(:invalid) end)
# err(:invalid)

ok(1) |> unwrap!()
# 1

err(:not_found) |> unwrap!()
# ** (Rustic.Result.UnhandledError) Expected an ok result, ":not_found" given.
```