Why choosing `unwrap_or_else` over `unwrap_or`? [duplicate]

Both are evaluated during the program’s execution and can be arbitrary values. The difference is that: With unwrap_or the fallback value is evaluated just before unwrap_or is called, and therefore is evaluated whether it’s needed or not (because Rust is an eager language). With unwrap_or_else the fallback value is evaluated only when unwrap_or_else triggers it … Read more

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