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errors5 solution

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mo8it
2024-06-26 18:21:19 +02:00
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rustlings-macros/info.toml
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@@ -692,24 +692,23 @@ name = "errors5"
dir = "13_error_handling"
test = false
hint = """
There are two different possible `Result` types produced within `main()`, which
are propagated using `?` operators. How do we declare a return type from
`main()` that allows both?
There are two different possible `Result` types produced within the `main`
function, which are propagated using the `?` operators. How do we declare a
return type for the `main` function that allows both?
Under the hood, the `?` operator calls `From::from` on the error value to
convert it to a boxed trait object, a `Box<dyn error::Error>`. This boxed trait
object is polymorphic, and since all errors implement the `error::Error` trait,
we can capture lots of different errors in one "Box" object.
convert it to a boxed trait object, a `Box<dyn Error>`. This boxed trait object
is polymorphic, and since all errors implement the `Error` trait, we can capture
lots of different errors in one `Box` object.
Check out this section of the book:
Check out this section of The Book:
https://doc.rust-lang.org/book/ch09-02-recoverable-errors-with-result.html#a-shortcut-for-propagating-errors-the--operator
Read more about boxing errors:
https://doc.rust-lang.org/stable/rust-by-example/error/multiple_error_types/boxing_errors.html
Read more about using the `?` operator with boxed errors:
https://doc.rust-lang.org/stable/rust-by-example/error/multiple_error_types/reenter_question_mark.html
"""
https://doc.rust-lang.org/stable/rust-by-example/error/multiple_error_types/reenter_question_mark.html"""
[[exercises]]
name = "errors6"