Fixed formatting error in GroupingMap::aggregate doc
@@ -56,7 +56,7 @@ impl<I, K, V> GroupingMap<I>
where I: Iterator<Item = (K, V)>,
K: Hash + Eq,
{
- /// This is the generic way to perform any operations on a `GroupingMap`.
+ /// This is the generic way to perform any operation on a `GroupingMap`.
/// It's suggested to use this method only to implement custom operations
/// when the already provided ones are not enough.
///
@@ -68,6 +68,7 @@ impl<I, K, V> GroupingMap<I>
/// - the current value of the accumulator of the group if there is currently one;
/// - a reference to the key of the group this element belongs to;
/// - the element from the source being aggregated;
+ ///
/// If `operation` returns `Some(element)` then the accumulator is updated with `element`,
/// otherwise the previous accumulation is discarded.
///
