Type Aliases

A type alias creates a name for another type. The two types can be used interchangeably.

// Copyright 2023 Google LLC
// SPDX-License-Identifier: Apache-2.0

enum CarryableConcreteItem {
    Left,
    Right,
}

type Item = CarryableConcreteItem;

// Aliases are more useful with long, complex types:
use std::cell::RefCell;
use std::sync::{Arc, RwLock};
type PlayerInventory = RwLock<Vec<Arc<RefCell<Item>>>>;

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A newtype is often a better alternative since it creates a distinct type. Prefer struct InventoryCount(usize) to type InventoryCount = usize.
C programmers will recognize this as similar to a typedef.