Best practices - Rust for C-Programmers

14.6 Best Practices

14.6.1 When to Use `Option`

Optional Function Returns: When a function may or may not return a value.
Data Structures: When modeling data structures that can have missing fields.
Configuration Settings: Representing optional configuration parameters.
Parsing and Validation: Handling scenarios where parsing might fail or data might be incomplete.

14.6.2 Avoiding Common Pitfalls

Overusing unwrap(): Relying on unwrap() can lead to panics. Prefer safer alternatives like match, unwrap_or(), unwrap_or_else(), or expect().
```
// Risky
let value = some_option.unwrap();
// Safer
let value = some_option.unwrap_or(default_value);
```
Ignoring None Cases: Always handle the None variant to maintain code safety and reliability.

Complex Nesting: Avoid deeply nested Option handling by leveraging combinators and early returns.

// Deeply nested (undesirable)
match a {
    Some(x) => match x.b {
        Some(y) => match y.c {
            Some(z) => Some(z),
            None => None,
        },
        None => None,
    },
    None => None,
}

// Using combinators (preferred)
a.and_then(|x| x.b).and_then(|y| y.c)