rust / intermediate
Snippet
Option<T> for Null Safety
Rust has no null values. Instead, Option<T> represents optional values: Some(T) contains a value, None represents absence. This makes null pointer exceptions impossible at compile time. The if let syntax provides convenient pattern matching, while unwrap_or offers a safe default fallback.
snippet.rs
rust
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fn find_user(id: u32) -> Option<&'static str> {match id {1 => Some("Alice"),2 => Some("Bob"),_ => None,}}fn main() {let user = find_user(1);if let Some(name) = user {println!("Found: {}", name);} else {println!("User not found");}// Using unwrap_or for default valueslet missing = find_user(999).unwrap_or("Guest");println!("Missing user: {}", missing);}
Breakdown
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fn find_user(id: u32) -> Option<&'static str>
Function returns Option — either Some(name) or None
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Some("Alice")
Wraps value in Some variant of Option
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_ => None
Wildcard pattern returns None for unmatched cases
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if let Some(name) = user { ... }
Conditional binding extracts value only if Some, avoiding explicit match
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.unwrap_or("Guest")
Returns contained value or provided default if None