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[](https://crates.io/crates/option-ext)
[](https://docs.rs/option-ext/)
# `option-ext`
## Introduction
This crate extends `Option` with additional methods, currently:
- `contains`
- `map_or2` (as a replacement for `map_or`)
- `map_or_else2` (as a replacement for `map_or_else`)
Its sister crate is [`result-ext`](https://github.com/soc/result-ext), which extends `Result`.
## Requirements
Rust 1.0 or newer.
## Usage
#### Dependency
Add the library as a dependency to your project by inserting
```toml
option-ext = "0.2.0"
```
into the `[dependencies]` section of your Cargo.toml file.
#### Example
```rust
use option_ext::OptionExt;
fn example_contains() {
let x: Option<u32> = Some(2);
assert_eq!(x.contains(&2), true);
let x: Option<u32> = Some(3);
assert_eq!(x.contains(&2), false);
let x: Option<u32> = None;
assert_eq!(x.contains(&2), false);
}
fn example_map_or2() {
let x = Some("bar");
assert_eq!(x.map_or2(|v| v.len(), 42), 3);
let x: Option<&str> = None;
assert_eq!(x.map_or2(|v| v.len(), 42), 42);
}
fn example_map_or_else2() {
let k = 23;
let x = Some("bar");
assert_eq!(x.map_or_else2(|v| v.len(), || 2 * k), 3);
let x: Option<&str> = None;
assert_eq!(x.map_or_else2(|v| v.len(), || 2 * k), 46);
}
```
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