rust - How do I convert a Vec lt;Result lt;T, E gt; gt; to Result lt;Vec lt;T gt;, E . . . You can use the FromIterator trait implementation on Result ( collect() requires FromIterator on the destination type and calls into it for the conversion from Iterator): fn vec_of_result_to_result_of_vec<T, E>(v: Vec<Result<T, E>>) -> Result<Vec<T>, E> { v into_iter() collect() }
Iterating over Results - Rust By Example - Learn Rust Result implements FromIterator so that a vector of results (Vec<Result<T, E>>) can be turned into a result with a vector (Result<Vec<T>, E>) Once an Result::Err is found, the iteration will terminate
Elegantly flatten Vec lt;Result lt;Vec lt;T gt;, E gt; gt; into Result lt;Vec lt;T gt;, E gt; I love how elegantly Rust can convert from Vec<Result< into Result<Vec< , but for more complex nested types I'm quickly finding myself in stinkier and stinkier code Is this as clean as it gets?: let a: Vec<i32> = vec![]; let b: Vec<Result<Vec<i32>, Error>> = a into_iter() map(|_| Ok(vec![])) collect::<Vec<_>>();
Unpacking some Rust ergonomics: getting a single Result from an . . . One of those bits of ergonomics that I love is how you can collect an iterable of Results into a Result of a Vec, effectively flipping the result inside out: you would expect a Vec<Result<T, E>>, and you can get a Result<Vec<T>, E> instead! The same thing applies for Option Let's see it in action
How to turn Vec lt;Result lt;_, _ gt; gt; into Result lt;Vec lt;_ gt;, _ gt;? : r rust - Reddit How can I turn this into a result which contains a vector or a single error message? Examples: What I'm looking for is similar to how Promise all ( [ ]) works in JavaScript the_vec into_iter() collect::<Result<Vec<_>, _>>() 10 votes, 10 comments I have a vector of results, which might contain errors
How to partition vector of results in Rust? - Stack Overflow The itertools crate has a dedicated method for partitioning an Iterator<Item = Result<T, E>> into a tuple of collections (Collection<T>, Collection<E>), where "Collection" can be your choice of type that implements the Extend trait, such as Vec or HashSet
std::result - Rust Result<T, E> is the type used for returning and propagating errors It is an enum with the variants, Ok(T), representing success and containing a value, and Err(E), representing error and containing an error value Ok(T), Err(E), Functions return Result whenever errors are expected and recoverable
Iteration patterns for Result Option - Karol Kuczmarskis Blog Using it to slice an iterable of Results is straightforward: let (oks, fails): (Vec<_>, Vec<_>) = results partition(Result::is_ok); The only thing that remains cumbersome is the fact that both parts of the resulting tuple still contain just Results
Iterating over Results - Rust By Example - rustwiki. org Result implements FromIterator so that a vector of results (Vec<Result<T, E>>) can be turned into a result with a vector (Result<Vec<T>, E>) Once an Result::Err is found, the iteration will terminate