Announcing Rust 1.76.0 | Rust Blog
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  • anlumo@feddit.deEnglish
    192·
    11 months ago

    Oh, inspect has finally arrived! That will help a ton with debug logging.

    • λλλ
      7·
      11 months ago

      Do you mind explaining? Maybe with the context of another languages equivalent?

      • anlumo@feddit.deEnglish
        152·
        11 months ago
        let bar: Result<T, E> = ...;
let foo = bar.inspect(|value| log::debug("{}", value));

        is equivalent to

        let bar: Result<T, E> = ...;
let foo = bar.map(|value| {
    log::debug("{}", value);
    value
});
        • xav
          1·
          11 months ago

          Warning: in the first case “value” is actually a shared reference, not a value.

      • GissaMittJobb@lemmy.ml
        2·
        11 months ago

        Looks vaguely like Stream::peek from Java, I think? There’s an equivalent method in Iterator::inspect.

      • owsei
        1·
        11 months ago

        it’s just a way to use map with a reference instead of the value, by what I understood.

        could be usefull for logging values in a Result so you can see it. However I think you can already do that by just mapping and returning the variable.