pub struct GroupBy<K, I, F>where
I: Iterator,{ /* private fields */ }
Expand description
GroupBy
is the storage for the lazy grouping operation.
If the groups are consumed in their original order, or if each
group is dropped without keeping it around, then GroupBy
uses
no allocations. It needs allocations only if several group iterators
are alive at the same time.
This type implements IntoIterator
(it is not an iterator
itself), because the group iterators need to borrow from this
value. It should be stored in a local variable or temporary and
iterated.
See .group_by()
for more information.
Trait Implementations§
source§impl<'a, K, I, F> IntoIterator for &'a GroupBy<K, I, F>
impl<'a, K, I, F> IntoIterator for &'a GroupBy<K, I, F>
Auto Trait Implementations§
impl<K, I, F> !RefUnwindSafe for GroupBy<K, I, F>
impl<K, I, F> Send for GroupBy<K, I, F>
impl<K, I, F> !Sync for GroupBy<K, I, F>
impl<K, I, F> Unpin for GroupBy<K, I, F>
impl<K, I, F> UnwindSafe for GroupBy<K, I, F>where
F: UnwindSafe,
I: UnwindSafe,
K: UnwindSafe,
<I as Iterator>::Item: UnwindSafe + RefUnwindSafe,
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
§impl<T> CompatExt for T
impl<T> CompatExt for T
§impl<T> Downcast for Twhere
T: Any,
impl<T> Downcast for Twhere
T: Any,
§fn into_any(self: Box<T>) -> Box<dyn Any>
fn into_any(self: Box<T>) -> Box<dyn Any>
Convert
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) to Box<dyn Any>
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