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Core Beginner

04 Strings & slices

Two string types: String owns its text, &str borrows a view of it. Slice out the first word, then build a fresh String from a borrowed one.

Step 1 / 2

Return the &str slice up to the first space in first_word -- the whole string if there's no space.

Hints

04_strings.rs

// the &str up to the first space, or the whole string if there is none
fn first_word(s: &str) -> &str {
    todo!()
}

// the &str up to the first space, or the whole string if there is none
fn first_word(s: &str) -> &str {
    todo!()
}

Reset to starterCompiled in a sandbox; hidden checks must pass.

Reveal solution

fn first_word(s: &str) -> &str {
    match s.find(' ') {
        Some(i) => &s[..i],
        None => s,
    }
}