library/core/src/unit.rs

   1 use crate::iter::FromIterator;
   2
   3 /// Collapses all unit items from an iterator into one.
   4 ///
   5 /// This is more useful when combined with higher-level abstractions, like
   6 /// collecting to a `Result<(), E>` where you only care about errors:
   7 ///
   8 /// ```
   9 /// use std::io::*;
  10 /// let data = vec![1, 2, 3, 4, 5];
  11 /// let res: Result<()> = data.iter()
  12 ///     .map(|x| writeln!(stdout(), "{}", x))
  13 ///     .collect();
  14 /// assert!(res.is_ok());
  15 /// ```
  16 #[stable(feature = "unit_from_iter", since = "1.23.0")]
  17 impl FromIterator<()> for () {
  18     fn from_iter<I: IntoIterator<Item = ()>>(iter: I) -> Self {
  19         iter.into_iter().for_each(|()| {})
  20     }
  21 }