Function frunk::semigroup::combine_all_option
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[src]
pub fn combine_all_option<T>(xs: &Vec<T>) -> Option<T> where T: Semigroup + Clone
Given a sequence of xs
, combine them and return the total
If the sequence is empty, returns None. Otherwise, returns Some(total).
let v1 = &vec![1, 2, 3]; assert_eq!(combine_all_option(v1), Some(6)); let v2: Vec<i16> = Vec::new(); // empty! assert_eq!(combine_all_option(&v2), None);Run