pub struct IndexSet<T, S = RandomState> { /* private fields */ }
Expand description
A hash set where the iteration order of the values is independent of their hash values.
The interface is closely compatible with the standard
HashSet
,
but also has additional features.
§Order
The values have a consistent order that is determined by the sequence of insertion and removal calls on the set. The order does not depend on the values or the hash function at all. Note that insertion order and value are not affected if a re-insertion is attempted once an element is already present.
All iterators traverse the set in order. Set operation iterators like
IndexSet::union
produce a concatenated order, as do their matching “bitwise”
operators. See their documentation for specifics.
The insertion order is preserved, with notable exceptions like the
.remove()
or .swap_remove()
methods.
Methods such as .sort_by()
of
course result in a new order, depending on the sorting order.
§Indices
The values are indexed in a compact range without holes in the range
0..self.len()
. For example, the method .get_full
looks up the index for
a value, and the method .get_index
looks up the value by index.
§Complexity
Internally, IndexSet<T, S>
just holds an IndexMap<T, (), S>
. Thus the complexity
of the two are the same for most methods.
§Examples
use indexmap::IndexSet;
// Collects which letters appear in a sentence.
let letters: IndexSet<_> = "a short treatise on fungi".chars().collect();
assert!(letters.contains(&'s'));
assert!(letters.contains(&'t'));
assert!(letters.contains(&'u'));
assert!(!letters.contains(&'y'));
Implementations§
source§impl<T> IndexSet<T>
impl<T> IndexSet<T>
sourcepub fn with_capacity(n: usize) -> Self
pub fn with_capacity(n: usize) -> Self
Create a new set with capacity for n
elements.
(Does not allocate if n
is zero.)
Computes in O(n) time.
source§impl<T, S> IndexSet<T, S>
impl<T, S> IndexSet<T, S>
sourcepub fn with_capacity_and_hasher(n: usize, hash_builder: S) -> Self
pub fn with_capacity_and_hasher(n: usize, hash_builder: S) -> Self
Create a new set with capacity for n
elements.
(Does not allocate if n
is zero.)
Computes in O(n) time.
sourcepub const fn with_hasher(hash_builder: S) -> Self
pub const fn with_hasher(hash_builder: S) -> Self
Create a new set with hash_builder
.
This function is const
, so it
can be called in static
contexts.
sourcepub fn capacity(&self) -> usize
pub fn capacity(&self) -> usize
Return the number of elements the set can hold without reallocating.
This number is a lower bound; the set might be able to hold more, but is guaranteed to be able to hold at least this many.
Computes in O(1) time.
sourcepub fn is_empty(&self) -> bool
pub fn is_empty(&self) -> bool
Returns true if the set contains no elements.
Computes in O(1) time.
sourcepub fn iter(&self) -> Iter<'_, T> ⓘ
pub fn iter(&self) -> Iter<'_, T> ⓘ
Return an iterator over the values of the set, in their order
sourcepub fn clear(&mut self)
pub fn clear(&mut self)
Remove all elements in the set, while preserving its capacity.
Computes in O(n) time.
sourcepub fn truncate(&mut self, len: usize)
pub fn truncate(&mut self, len: usize)
Shortens the set, keeping the first len
elements and dropping the rest.
If len
is greater than the set’s current length, this has no effect.
sourcepub fn drain<R>(&mut self, range: R) -> Drain<'_, T> ⓘwhere
R: RangeBounds<usize>,
pub fn drain<R>(&mut self, range: R) -> Drain<'_, T> ⓘwhere
R: RangeBounds<usize>,
Clears the IndexSet
in the given index range, returning those values
as a drain iterator.
The range may be any type that implements RangeBounds<usize>
,
including all of the std::ops::Range*
types, or even a tuple pair of
Bound
start and end values. To drain the set entirely, use RangeFull
like set.drain(..)
.
This shifts down all entries following the drained range to fill the gap, and keeps the allocated memory for reuse.
Panics if the starting point is greater than the end point or if the end point is greater than the length of the set.
sourcepub fn split_off(&mut self, at: usize) -> Selfwhere
S: Clone,
pub fn split_off(&mut self, at: usize) -> Selfwhere
S: Clone,
Splits the collection into two at the given index.
Returns a newly allocated set containing the elements in the range
[at, len)
. After the call, the original set will be left containing
the elements [0, at)
with its previous capacity unchanged.
Panics if at > len
.
sourcepub fn reserve(&mut self, additional: usize)
pub fn reserve(&mut self, additional: usize)
Reserve capacity for additional
more values.
Computes in O(n) time.
sourcepub fn reserve_exact(&mut self, additional: usize)
pub fn reserve_exact(&mut self, additional: usize)
Reserve capacity for additional
more values, without over-allocating.
Unlike reserve
, this does not deliberately over-allocate the entry capacity to avoid
frequent re-allocations. However, the underlying data structures may still have internal
capacity requirements, and the allocator itself may give more space than requested, so this
cannot be relied upon to be precisely minimal.
Computes in O(n) time.
sourcepub fn try_reserve(&mut self, additional: usize) -> Result<(), TryReserveError>
pub fn try_reserve(&mut self, additional: usize) -> Result<(), TryReserveError>
Try to reserve capacity for additional
more values.
Computes in O(n) time.
sourcepub fn try_reserve_exact(
&mut self,
additional: usize,
) -> Result<(), TryReserveError>
pub fn try_reserve_exact( &mut self, additional: usize, ) -> Result<(), TryReserveError>
Try to reserve capacity for additional
more values, without over-allocating.
Unlike try_reserve
, this does not deliberately over-allocate the entry capacity to avoid
frequent re-allocations. However, the underlying data structures may still have internal
capacity requirements, and the allocator itself may give more space than requested, so this
cannot be relied upon to be precisely minimal.
Computes in O(n) time.
sourcepub fn shrink_to_fit(&mut self)
pub fn shrink_to_fit(&mut self)
Shrink the capacity of the set as much as possible.
Computes in O(n) time.
source§impl<T, S> IndexSet<T, S>
impl<T, S> IndexSet<T, S>
sourcepub fn insert(&mut self, value: T) -> bool
pub fn insert(&mut self, value: T) -> bool
Insert the value into the set.
If an equivalent item already exists in the set, it returns
false
leaving the original value in the set and without
altering its insertion order. Otherwise, it inserts the new
item and returns true
.
Computes in O(1) time (amortized average).
sourcepub fn insert_full(&mut self, value: T) -> (usize, bool)
pub fn insert_full(&mut self, value: T) -> (usize, bool)
Insert the value into the set, and get its index.
If an equivalent item already exists in the set, it returns
the index of the existing item and false
, leaving the
original value in the set and without altering its insertion
order. Otherwise, it inserts the new item and returns the index
of the inserted item and true
.
Computes in O(1) time (amortized average).
sourcepub fn insert_sorted(&mut self, value: T) -> (usize, bool)where
T: Ord,
pub fn insert_sorted(&mut self, value: T) -> (usize, bool)where
T: Ord,
Insert the value into the set at its ordered position among sorted values.
This is equivalent to finding the position with
binary_search
, and if needed calling
insert_before
for a new value.
If the sorted item is found in the set, it returns the index of that
existing item and false
, without any change. Otherwise, it inserts the
new item and returns its sorted index and true
.
If the existing items are not already sorted, then the insertion
index is unspecified (like slice::binary_search
), but the value
is moved to or inserted at that position regardless.
Computes in O(n) time (average). Instead of repeating calls to
insert_sorted
, it may be faster to call batched insert
or extend
and only call sort
or
sort_unstable
once.
sourcepub fn insert_before(&mut self, index: usize, value: T) -> (usize, bool)
pub fn insert_before(&mut self, index: usize, value: T) -> (usize, bool)
Insert the value into the set before the value at the given index, or at the end.
If an equivalent item already exists in the set, it returns false
leaving the
original value in the set, but moved to the new position. The returned index
will either be the given index or one less, depending on how the value moved.
(See shift_insert
for different behavior here.)
Otherwise, it inserts the new value exactly at the given index and returns true
.
Panics if index
is out of bounds.
Valid indices are 0..=set.len()
(inclusive).
Computes in O(n) time (average).
§Examples
use indexmap::IndexSet;
let mut set: IndexSet<char> = ('a'..='z').collect();
// The new value '*' goes exactly at the given index.
assert_eq!(set.get_index_of(&'*'), None);
assert_eq!(set.insert_before(10, '*'), (10, true));
assert_eq!(set.get_index_of(&'*'), Some(10));
// Moving the value 'a' up will shift others down, so this moves *before* 10 to index 9.
assert_eq!(set.insert_before(10, 'a'), (9, false));
assert_eq!(set.get_index_of(&'a'), Some(9));
assert_eq!(set.get_index_of(&'*'), Some(10));
// Moving the value 'z' down will shift others up, so this moves to exactly 10.
assert_eq!(set.insert_before(10, 'z'), (10, false));
assert_eq!(set.get_index_of(&'z'), Some(10));
assert_eq!(set.get_index_of(&'*'), Some(11));
// Moving or inserting before the endpoint is also valid.
assert_eq!(set.len(), 27);
assert_eq!(set.insert_before(set.len(), '*'), (26, false));
assert_eq!(set.get_index_of(&'*'), Some(26));
assert_eq!(set.insert_before(set.len(), '+'), (27, true));
assert_eq!(set.get_index_of(&'+'), Some(27));
assert_eq!(set.len(), 28);
sourcepub fn shift_insert(&mut self, index: usize, value: T) -> bool
pub fn shift_insert(&mut self, index: usize, value: T) -> bool
Insert the value into the set at the given index.
If an equivalent item already exists in the set, it returns false
leaving
the original value in the set, but moved to the given index.
Note that existing values cannot be moved to index == set.len()
!
(See insert_before
for different behavior here.)
Otherwise, it inserts the new value at the given index and returns true
.
Panics if index
is out of bounds.
Valid indices are 0..set.len()
(exclusive) when moving an existing value, or
0..=set.len()
(inclusive) when inserting a new value.
Computes in O(n) time (average).
§Examples
use indexmap::IndexSet;
let mut set: IndexSet<char> = ('a'..='z').collect();
// The new value '*' goes exactly at the given index.
assert_eq!(set.get_index_of(&'*'), None);
assert_eq!(set.shift_insert(10, '*'), true);
assert_eq!(set.get_index_of(&'*'), Some(10));
// Moving the value 'a' up to 10 will shift others down, including the '*' that was at 10.
assert_eq!(set.shift_insert(10, 'a'), false);
assert_eq!(set.get_index_of(&'a'), Some(10));
assert_eq!(set.get_index_of(&'*'), Some(9));
// Moving the value 'z' down to 9 will shift others up, including the '*' that was at 9.
assert_eq!(set.shift_insert(9, 'z'), false);
assert_eq!(set.get_index_of(&'z'), Some(9));
assert_eq!(set.get_index_of(&'*'), Some(10));
// Existing values can move to len-1 at most, but new values can insert at the endpoint.
assert_eq!(set.len(), 27);
assert_eq!(set.shift_insert(set.len() - 1, '*'), false);
assert_eq!(set.get_index_of(&'*'), Some(26));
assert_eq!(set.shift_insert(set.len(), '+'), true);
assert_eq!(set.get_index_of(&'+'), Some(27));
assert_eq!(set.len(), 28);
use indexmap::IndexSet;
let mut set: IndexSet<char> = ('a'..='z').collect();
// This is an invalid index for moving an existing value!
set.shift_insert(set.len(), 'a');
sourcepub fn replace(&mut self, value: T) -> Option<T>
pub fn replace(&mut self, value: T) -> Option<T>
Adds a value to the set, replacing the existing value, if any, that is equal to the given one, without altering its insertion order. Returns the replaced value.
Computes in O(1) time (average).
sourcepub fn replace_full(&mut self, value: T) -> (usize, Option<T>)
pub fn replace_full(&mut self, value: T) -> (usize, Option<T>)
Adds a value to the set, replacing the existing value, if any, that is equal to the given one, without altering its insertion order. Returns the index of the item and its replaced value.
Computes in O(1) time (average).
sourcepub fn difference<'a, S2>(
&'a self,
other: &'a IndexSet<T, S2>,
) -> Difference<'a, T, S2> ⓘwhere
S2: BuildHasher,
pub fn difference<'a, S2>(
&'a self,
other: &'a IndexSet<T, S2>,
) -> Difference<'a, T, S2> ⓘwhere
S2: BuildHasher,
Return an iterator over the values that are in self
but not other
.
Values are produced in the same order that they appear in self
.
sourcepub fn symmetric_difference<'a, S2>(
&'a self,
other: &'a IndexSet<T, S2>,
) -> SymmetricDifference<'a, T, S, S2> ⓘwhere
S2: BuildHasher,
pub fn symmetric_difference<'a, S2>(
&'a self,
other: &'a IndexSet<T, S2>,
) -> SymmetricDifference<'a, T, S, S2> ⓘwhere
S2: BuildHasher,
Return an iterator over the values that are in self
or other
,
but not in both.
Values from self
are produced in their original order, followed by
values from other
in their original order.
sourcepub fn intersection<'a, S2>(
&'a self,
other: &'a IndexSet<T, S2>,
) -> Intersection<'a, T, S2> ⓘwhere
S2: BuildHasher,
pub fn intersection<'a, S2>(
&'a self,
other: &'a IndexSet<T, S2>,
) -> Intersection<'a, T, S2> ⓘwhere
S2: BuildHasher,
Return an iterator over the values that are in both self
and other
.
Values are produced in the same order that they appear in self
.
sourcepub fn union<'a, S2>(&'a self, other: &'a IndexSet<T, S2>) -> Union<'a, T, S> ⓘwhere
S2: BuildHasher,
pub fn union<'a, S2>(&'a self, other: &'a IndexSet<T, S2>) -> Union<'a, T, S> ⓘwhere
S2: BuildHasher,
Return an iterator over all values that are in self
or other
.
Values from self
are produced in their original order, followed by
values that are unique to other
in their original order.
sourcepub fn splice<R, I>(
&mut self,
range: R,
replace_with: I,
) -> Splice<'_, I::IntoIter, T, S> ⓘ
pub fn splice<R, I>( &mut self, range: R, replace_with: I, ) -> Splice<'_, I::IntoIter, T, S> ⓘ
Creates a splicing iterator that replaces the specified range in the set
with the given replace_with
iterator and yields the removed items.
replace_with
does not need to be the same length as range
.
The range
is removed even if the iterator is not consumed until the
end. It is unspecified how many elements are removed from the set if the
Splice
value is leaked.
The input iterator replace_with
is only consumed when the Splice
value is dropped. If a value from the iterator matches an existing entry
in the set (outside of range
), then the original will be unchanged.
Otherwise, the new value will be inserted in the replaced range
.
Panics if the starting point is greater than the end point or if the end point is greater than the length of the set.
§Examples
use indexmap::IndexSet;
let mut set = IndexSet::from([0, 1, 2, 3, 4]);
let new = [5, 4, 3, 2, 1];
let removed: Vec<_> = set.splice(2..4, new).collect();
// 1 and 4 kept their positions, while 5, 3, and 2 were newly inserted.
assert!(set.into_iter().eq([0, 1, 5, 3, 2, 4]));
assert_eq!(removed, &[2, 3]);
sourcepub fn append<S2>(&mut self, other: &mut IndexSet<T, S2>)
pub fn append<S2>(&mut self, other: &mut IndexSet<T, S2>)
Moves all values from other
into self
, leaving other
empty.
This is equivalent to calling insert
for each value
from other
in order, which means that values that already exist
in self
are unchanged in their current position.
See also union
to iterate the combined values by
reference, without modifying self
or other
.
§Examples
use indexmap::IndexSet;
let mut a = IndexSet::from([3, 2, 1]);
let mut b = IndexSet::from([3, 4, 5]);
let old_capacity = b.capacity();
a.append(&mut b);
assert_eq!(a.len(), 5);
assert_eq!(b.len(), 0);
assert_eq!(b.capacity(), old_capacity);
assert!(a.iter().eq(&[3, 2, 1, 4, 5]));
source§impl<T, S> IndexSet<T, S>where
S: BuildHasher,
impl<T, S> IndexSet<T, S>where
S: BuildHasher,
sourcepub fn contains<Q>(&self, value: &Q) -> bool
pub fn contains<Q>(&self, value: &Q) -> bool
Return true
if an equivalent to value
exists in the set.
Computes in O(1) time (average).
sourcepub fn get<Q>(&self, value: &Q) -> Option<&T>
pub fn get<Q>(&self, value: &Q) -> Option<&T>
Return a reference to the value stored in the set, if it is present,
else None
.
Computes in O(1) time (average).
sourcepub fn get_index_of<Q>(&self, value: &Q) -> Option<usize>
pub fn get_index_of<Q>(&self, value: &Q) -> Option<usize>
Return item index, if it exists in the set
Computes in O(1) time (average).
sourcepub fn remove<Q>(&mut self, value: &Q) -> bool
👎Deprecated: remove
disrupts the set order – use swap_remove
or shift_remove
for explicit behavior.
pub fn remove<Q>(&mut self, value: &Q) -> bool
remove
disrupts the set order – use swap_remove
or shift_remove
for explicit behavior.Remove the value from the set, and return true
if it was present.
NOTE: This is equivalent to .swap_remove(value)
, replacing this
value’s position with the last element, and it is deprecated in favor of calling that
explicitly. If you need to preserve the relative order of the values in the set, use
.shift_remove(value)
instead.
sourcepub fn swap_remove<Q>(&mut self, value: &Q) -> bool
pub fn swap_remove<Q>(&mut self, value: &Q) -> bool
Remove the value from the set, and return true
if it was present.
Like Vec::swap_remove
, the value is removed by swapping it with the
last element of the set and popping it off. This perturbs
the position of what used to be the last element!
Return false
if value
was not in the set.
Computes in O(1) time (average).
sourcepub fn shift_remove<Q>(&mut self, value: &Q) -> bool
pub fn shift_remove<Q>(&mut self, value: &Q) -> bool
Remove the value from the set, and return true
if it was present.
Like Vec::remove
, the value is removed by shifting all of the
elements that follow it, preserving their relative order.
This perturbs the index of all of those elements!
Return false
if value
was not in the set.
Computes in O(n) time (average).
sourcepub fn take<Q>(&mut self, value: &Q) -> Option<T>
👎Deprecated: take
disrupts the set order – use swap_take
or shift_take
for explicit behavior.
pub fn take<Q>(&mut self, value: &Q) -> Option<T>
take
disrupts the set order – use swap_take
or shift_take
for explicit behavior.Removes and returns the value in the set, if any, that is equal to the given one.
NOTE: This is equivalent to .swap_take(value)
, replacing this
value’s position with the last element, and it is deprecated in favor of calling that
explicitly. If you need to preserve the relative order of the values in the set, use
.shift_take(value)
instead.
sourcepub fn swap_take<Q>(&mut self, value: &Q) -> Option<T>
pub fn swap_take<Q>(&mut self, value: &Q) -> Option<T>
Removes and returns the value in the set, if any, that is equal to the given one.
Like Vec::swap_remove
, the value is removed by swapping it with the
last element of the set and popping it off. This perturbs
the position of what used to be the last element!
Return None
if value
was not in the set.
Computes in O(1) time (average).
sourcepub fn shift_take<Q>(&mut self, value: &Q) -> Option<T>
pub fn shift_take<Q>(&mut self, value: &Q) -> Option<T>
Removes and returns the value in the set, if any, that is equal to the given one.
Like Vec::remove
, the value is removed by shifting all of the
elements that follow it, preserving their relative order.
This perturbs the index of all of those elements!
Return None
if value
was not in the set.
Computes in O(n) time (average).
sourcepub fn swap_remove_full<Q>(&mut self, value: &Q) -> Option<(usize, T)>
pub fn swap_remove_full<Q>(&mut self, value: &Q) -> Option<(usize, T)>
Remove the value from the set return it and the index it had.
Like Vec::swap_remove
, the value is removed by swapping it with the
last element of the set and popping it off. This perturbs
the position of what used to be the last element!
Return None
if value
was not in the set.
sourcepub fn shift_remove_full<Q>(&mut self, value: &Q) -> Option<(usize, T)>
pub fn shift_remove_full<Q>(&mut self, value: &Q) -> Option<(usize, T)>
Remove the value from the set return it and the index it had.
Like Vec::remove
, the value is removed by shifting all of the
elements that follow it, preserving their relative order.
This perturbs the index of all of those elements!
Return None
if value
was not in the set.
source§impl<T, S> IndexSet<T, S>
impl<T, S> IndexSet<T, S>
sourcepub fn pop(&mut self) -> Option<T>
pub fn pop(&mut self) -> Option<T>
Remove the last value
This preserves the order of the remaining elements.
Computes in O(1) time (average).
sourcepub fn retain<F>(&mut self, keep: F)
pub fn retain<F>(&mut self, keep: F)
Scan through each value in the set and keep those where the
closure keep
returns true
.
The elements are visited in order, and remaining elements keep their order.
Computes in O(n) time (average).
sourcepub fn sort(&mut self)where
T: Ord,
pub fn sort(&mut self)where
T: Ord,
Sort the set’s values by their default ordering.
This is a stable sort – but equivalent values should not normally coexist in
a set at all, so sort_unstable
is preferred
because it is generally faster and doesn’t allocate auxiliary memory.
See sort_by
for details.
sourcepub fn sort_by<F>(&mut self, cmp: F)
pub fn sort_by<F>(&mut self, cmp: F)
Sort the set’s values in place using the comparison function cmp
.
Computes in O(n log n) time and O(n) space. The sort is stable.
sourcepub fn sorted_by<F>(self, cmp: F) -> IntoIter<T> ⓘ
pub fn sorted_by<F>(self, cmp: F) -> IntoIter<T> ⓘ
Sort the values of the set and return a by-value iterator of the values with the result.
The sort is stable.
sourcepub fn sort_unstable(&mut self)where
T: Ord,
pub fn sort_unstable(&mut self)where
T: Ord,
Sort the set’s values by their default ordering.
See sort_unstable_by
for details.
sourcepub fn sort_unstable_by<F>(&mut self, cmp: F)
pub fn sort_unstable_by<F>(&mut self, cmp: F)
Sort the set’s values in place using the comparison function cmp
.
Computes in O(n log n) time. The sort is unstable.
sourcepub fn sorted_unstable_by<F>(self, cmp: F) -> IntoIter<T> ⓘ
pub fn sorted_unstable_by<F>(self, cmp: F) -> IntoIter<T> ⓘ
Sort the values of the set and return a by-value iterator of the values with the result.
sourcepub fn sort_by_cached_key<K, F>(&mut self, sort_key: F)
pub fn sort_by_cached_key<K, F>(&mut self, sort_key: F)
Sort the set’s values in place using a key extraction function.
During sorting, the function is called at most once per entry, by using temporary storage
to remember the results of its evaluation. The order of calls to the function is
unspecified and may change between versions of indexmap
or the standard library.
Computes in O(m n + n log n + c) time () and O(n) space, where the function is O(m), n is the length of the map, and c the capacity. The sort is stable.
sourcepub fn binary_search(&self, x: &T) -> Result<usize, usize>where
T: Ord,
pub fn binary_search(&self, x: &T) -> Result<usize, usize>where
T: Ord,
Search over a sorted set for a value.
Returns the position where that value is present, or the position where it can be inserted
to maintain the sort. See slice::binary_search
for more details.
Computes in O(log(n)) time, which is notably less scalable than looking the value up
using get_index_of
, but this can also position missing values.
sourcepub fn binary_search_by<'a, F>(&'a self, f: F) -> Result<usize, usize>
pub fn binary_search_by<'a, F>(&'a self, f: F) -> Result<usize, usize>
Search over a sorted set with a comparator function.
Returns the position where that value is present, or the position where it can be inserted
to maintain the sort. See slice::binary_search_by
for more details.
Computes in O(log(n)) time.
sourcepub fn binary_search_by_key<'a, B, F>(
&'a self,
b: &B,
f: F,
) -> Result<usize, usize>
pub fn binary_search_by_key<'a, B, F>( &'a self, b: &B, f: F, ) -> Result<usize, usize>
Search over a sorted set with an extraction function.
Returns the position where that value is present, or the position where it can be inserted
to maintain the sort. See slice::binary_search_by_key
for more details.
Computes in O(log(n)) time.
sourcepub fn partition_point<P>(&self, pred: P) -> usize
pub fn partition_point<P>(&self, pred: P) -> usize
Returns the index of the partition point of a sorted set according to the given predicate (the index of the first element of the second partition).
See slice::partition_point
for more details.
Computes in O(log(n)) time.
sourcepub fn reverse(&mut self)
pub fn reverse(&mut self)
Reverses the order of the set’s values in place.
Computes in O(n) time and O(1) space.
sourcepub fn as_slice(&self) -> &Slice<T>
pub fn as_slice(&self) -> &Slice<T>
Returns a slice of all the values in the set.
Computes in O(1) time.
sourcepub fn into_boxed_slice(self) -> Box<Slice<T>>
pub fn into_boxed_slice(self) -> Box<Slice<T>>
Converts into a boxed slice of all the values in the set.
Note that this will drop the inner hash table and any excess capacity.
sourcepub fn get_index(&self, index: usize) -> Option<&T>
pub fn get_index(&self, index: usize) -> Option<&T>
Get a value by index
Valid indices are 0 <= index < self.len()
.
Computes in O(1) time.
sourcepub fn get_range<R: RangeBounds<usize>>(&self, range: R) -> Option<&Slice<T>>
pub fn get_range<R: RangeBounds<usize>>(&self, range: R) -> Option<&Slice<T>>
Returns a slice of values in the given range of indices.
Valid indices are 0 <= index < self.len()
.
Computes in O(1) time.
sourcepub fn swap_remove_index(&mut self, index: usize) -> Option<T>
pub fn swap_remove_index(&mut self, index: usize) -> Option<T>
Remove the value by index
Valid indices are 0 <= index < self.len()
.
Like Vec::swap_remove
, the value is removed by swapping it with the
last element of the set and popping it off. This perturbs
the position of what used to be the last element!
Computes in O(1) time (average).
sourcepub fn shift_remove_index(&mut self, index: usize) -> Option<T>
pub fn shift_remove_index(&mut self, index: usize) -> Option<T>
Remove the value by index
Valid indices are 0 <= index < self.len()
.
Like Vec::remove
, the value is removed by shifting all of the
elements that follow it, preserving their relative order.
This perturbs the index of all of those elements!
Computes in O(n) time (average).
sourcepub fn move_index(&mut self, from: usize, to: usize)
pub fn move_index(&mut self, from: usize, to: usize)
Moves the position of a value from one index to another by shifting all other values in-between.
- If
from < to
, the other values will shift down while the targeted value moves up. - If
from > to
, the other values will shift up while the targeted value moves down.
Panics if from
or to
are out of bounds.
Computes in O(n) time (average).
sourcepub fn swap_indices(&mut self, a: usize, b: usize)
pub fn swap_indices(&mut self, a: usize, b: usize)
Swaps the position of two values in the set.
Panics if a
or b
are out of bounds.
Computes in O(1) time (average).
source§impl<T, S> IndexSet<T, S>
impl<T, S> IndexSet<T, S>
sourcepub fn is_disjoint<S2>(&self, other: &IndexSet<T, S2>) -> boolwhere
S2: BuildHasher,
pub fn is_disjoint<S2>(&self, other: &IndexSet<T, S2>) -> boolwhere
S2: BuildHasher,
Returns true
if self
has no elements in common with other
.
sourcepub fn is_subset<S2>(&self, other: &IndexSet<T, S2>) -> boolwhere
S2: BuildHasher,
pub fn is_subset<S2>(&self, other: &IndexSet<T, S2>) -> boolwhere
S2: BuildHasher,
Returns true
if all elements of self
are contained in other
.
sourcepub fn is_superset<S2>(&self, other: &IndexSet<T, S2>) -> boolwhere
S2: BuildHasher,
pub fn is_superset<S2>(&self, other: &IndexSet<T, S2>) -> boolwhere
S2: BuildHasher,
Returns true
if all elements of other
are contained in self
.
Trait Implementations§
source§impl<T, S1, S2> BitOr<&IndexSet<T, S2>> for &IndexSet<T, S1>
impl<T, S1, S2> BitOr<&IndexSet<T, S2>> for &IndexSet<T, S1>
source§impl<T, S1, S2> BitXor<&IndexSet<T, S2>> for &IndexSet<T, S1>
impl<T, S1, S2> BitXor<&IndexSet<T, S2>> for &IndexSet<T, S1>
source§impl<'de, T, S> Deserialize<'de> for IndexSet<T, S>
impl<'de, T, S> Deserialize<'de> for IndexSet<T, S>
source§fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>where
D: Deserializer<'de>,
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>where
D: Deserializer<'de>,
source§impl<'a, T, S> Extend<&'a T> for IndexSet<T, S>
impl<'a, T, S> Extend<&'a T> for IndexSet<T, S>
source§fn extend<I: IntoIterator<Item = &'a T>>(&mut self, iterable: I)
fn extend<I: IntoIterator<Item = &'a T>>(&mut self, iterable: I)
source§fn extend_one(&mut self, item: A)
fn extend_one(&mut self, item: A)
extend_one
)source§fn extend_reserve(&mut self, additional: usize)
fn extend_reserve(&mut self, additional: usize)
extend_one
)source§impl<T, S> Extend<T> for IndexSet<T, S>
impl<T, S> Extend<T> for IndexSet<T, S>
source§fn extend<I: IntoIterator<Item = T>>(&mut self, iterable: I)
fn extend<I: IntoIterator<Item = T>>(&mut self, iterable: I)
source§fn extend_one(&mut self, item: A)
fn extend_one(&mut self, item: A)
extend_one
)source§fn extend_reserve(&mut self, additional: usize)
fn extend_reserve(&mut self, additional: usize)
extend_one
)source§impl<T, S> FromIterator<T> for IndexSet<T, S>
impl<T, S> FromIterator<T> for IndexSet<T, S>
source§fn from_iter<I: IntoIterator<Item = T>>(iterable: I) -> Self
fn from_iter<I: IntoIterator<Item = T>>(iterable: I) -> Self
source§impl<T, S> Index<usize> for IndexSet<T, S>
impl<T, S> Index<usize> for IndexSet<T, S>
Access IndexSet
values at indexed positions.
§Examples
use indexmap::IndexSet;
let mut set = IndexSet::new();
for word in "Lorem ipsum dolor sit amet".split_whitespace() {
set.insert(word.to_string());
}
assert_eq!(set[0], "Lorem");
assert_eq!(set[1], "ipsum");
set.reverse();
assert_eq!(set[0], "amet");
assert_eq!(set[1], "sit");
set.sort();
assert_eq!(set[0], "Lorem");
assert_eq!(set[1], "amet");
use indexmap::IndexSet;
let mut set = IndexSet::new();
set.insert("foo");
println!("{:?}", set[10]); // panics!
source§impl<'de, T, S, E> IntoDeserializer<'de, E> for IndexSet<T, S>
impl<'de, T, S, E> IntoDeserializer<'de, E> for IndexSet<T, S>
§type Deserializer = SeqDeserializer<<IndexSet<T, S> as IntoIterator>::IntoIter, E>
type Deserializer = SeqDeserializer<<IndexSet<T, S> as IntoIterator>::IntoIter, E>
source§fn into_deserializer(self) -> Self::Deserializer
fn into_deserializer(self) -> Self::Deserializer
source§impl<'a, T, S> IntoIterator for &'a IndexSet<T, S>
impl<'a, T, S> IntoIterator for &'a IndexSet<T, S>
source§impl<T, S> IntoIterator for IndexSet<T, S>
impl<T, S> IntoIterator for IndexSet<T, S>
source§impl<T, S> MutableValues for IndexSet<T, S>where
S: BuildHasher,
impl<T, S> MutableValues for IndexSet<T, S>where
S: BuildHasher,
Opt-in mutable access to IndexSet
values.
See MutableValues
for more information.
source§impl<T, S1, S2> PartialEq<IndexSet<T, S2>> for IndexSet<T, S1>
impl<T, S1, S2> PartialEq<IndexSet<T, S2>> for IndexSet<T, S1>
impl<T, S> Eq for IndexSet<T, S>
Auto Trait Implementations§
impl<T, S> Freeze for IndexSet<T, S>where
S: Freeze,
impl<T, S> RefUnwindSafe for IndexSet<T, S>where
S: RefUnwindSafe,
T: RefUnwindSafe,
impl<T, S> Send for IndexSet<T, S>
impl<T, S> Sync for IndexSet<T, S>
impl<T, S> Unpin for IndexSet<T, S>
impl<T, S> UnwindSafe for IndexSet<T, S>where
S: UnwindSafe,
T: UnwindSafe,
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
source§impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
source§default unsafe fn clone_to_uninit(&self, dst: *mut T)
default unsafe fn clone_to_uninit(&self, dst: *mut T)
clone_to_uninit
)source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
source§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key
and return true
if they are equal.