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The curriculum, drills, tutor, and interviewer mode are for readers of Ace the Rust Interview. The code is printed in the Preface (Companion site access).

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beginner · order 10

Propagate with ?

opt-qmark-01Related book chapters: 2, 8 (optional — this page is complete on its own)Resultquestion-mark

Slug: opt-qmark-01 · Paired reading: Chapters 2 and 8

Prompt

Implement fn sum_parsed(a: &str, b: &str) -> Result<i32, std::num::ParseIntError> using ?. No manual match on the parse results.