rust / beginner
Snippet
Handling Optional Values with Option
Option<T> represents a value that might exist or not, avoiding null references. Some contains a value, None represents absence. The if let syntax provides concise pattern matching, while unwrap_or provides a default value.
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);}let unknown = find_user(999);println!("User: {:?}", unknown.unwrap_or("Guest"));}
Breakdown
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fn find_user(id: u32) -> Option<&'static str>
Returns Some(name) or None depending on id
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if let Some(name) = user
Executes block only if user is Some, binds value to name
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unwrap_or("Guest")
Returns the value inside Some, or the default if None