pub struct Range<Idx> {
pub start: Idx,
pub end: Idx,
}
Expand description
A (half-open) range bounded inclusively below and exclusively above
(start..end
).
The range start..end
contains all values with start <= x < end
.
It is empty if start >= end
.
Examples
The start..end
syntax is a Range
:
assert_eq!((3..5), std::ops::Range { start: 3, end: 5 });
assert_eq!(3 + 4 + 5, (3..6).sum());
Runlet arr = [0, 1, 2, 3, 4];
assert_eq!(arr[ .. ], [0, 1, 2, 3, 4]);
assert_eq!(arr[ .. 3], [0, 1, 2 ]);
assert_eq!(arr[ ..=3], [0, 1, 2, 3 ]);
assert_eq!(arr[1.. ], [ 1, 2, 3, 4]);
assert_eq!(arr[1.. 3], [ 1, 2 ]); // This is a `Range`
assert_eq!(arr[1..=3], [ 1, 2, 3 ]);
RunFields§
§start: Idx
The lower bound of the range (inclusive).
end: Idx
The upper bound of the range (exclusive).
Implementations§
source§impl<Idx: PartialOrd<Idx>> Range<Idx>
impl<Idx: PartialOrd<Idx>> Range<Idx>
1.35.0 · sourcepub fn contains<U>(&self, item: &U) -> bool
pub fn contains<U>(&self, item: &U) -> bool
Returns true
if item
is contained in the range.
Examples
assert!(!(3..5).contains(&2));
assert!( (3..5).contains(&3));
assert!( (3..5).contains(&4));
assert!(!(3..5).contains(&5));
assert!(!(3..3).contains(&3));
assert!(!(3..2).contains(&3));
assert!( (0.0..1.0).contains(&0.5));
assert!(!(0.0..1.0).contains(&f32::NAN));
assert!(!(0.0..f32::NAN).contains(&0.5));
assert!(!(f32::NAN..1.0).contains(&0.5));
Run1.47.0 · sourcepub fn is_empty(&self) -> bool
pub fn is_empty(&self) -> bool
Returns true
if the range contains no items.
Examples
assert!(!(3..5).is_empty());
assert!( (3..3).is_empty());
assert!( (3..2).is_empty());
RunThe range is empty if either side is incomparable:
assert!(!(3.0..5.0).is_empty());
assert!( (3.0..f32::NAN).is_empty());
assert!( (f32::NAN..5.0).is_empty());
RunTrait Implementations§
source§impl<A: Step> DoubleEndedIterator for Range<A>
impl<A: Step> DoubleEndedIterator for Range<A>
source§fn next_back(&mut self) -> Option<A>
fn next_back(&mut self) -> Option<A>
source§fn nth_back(&mut self, n: usize) -> Option<A>
fn nth_back(&mut self, n: usize) -> Option<A>
n
th element from the end of the iterator. Read moresource§fn advance_back_by(&mut self, n: usize) -> Result<(), NonZeroUsize>
fn advance_back_by(&mut self, n: usize) -> Result<(), NonZeroUsize>
iter_advance_by
#77404)n
elements. Read more1.27.0 · source§fn try_rfold<B, F, R>(&mut self, init: B, f: F) -> R
fn try_rfold<B, F, R>(&mut self, init: B, f: F) -> R
Iterator::try_fold()
: it takes
elements starting from the back of the iterator. Read moresource§impl ExactSizeIterator for Range<i16>
impl ExactSizeIterator for Range<i16>
source§impl ExactSizeIterator for Range<i32>
impl ExactSizeIterator for Range<i32>
source§impl ExactSizeIterator for Range<i8>
impl ExactSizeIterator for Range<i8>
source§impl ExactSizeIterator for Range<isize>
impl ExactSizeIterator for Range<isize>
source§impl ExactSizeIterator for Range<u16>
impl ExactSizeIterator for Range<u16>
source§impl ExactSizeIterator for Range<u32>
impl ExactSizeIterator for Range<u32>
source§impl ExactSizeIterator for Range<u8>
impl ExactSizeIterator for Range<u8>
source§impl ExactSizeIterator for Range<usize>
impl ExactSizeIterator for Range<usize>
source§impl<A: Step> Iterator for Range<A>
impl<A: Step> Iterator for Range<A>
source§fn size_hint(&self) -> (usize, Option<usize>)
fn size_hint(&self) -> (usize, Option<usize>)
source§fn count(self) -> usize
fn count(self) -> usize
source§fn is_sorted(self) -> bool
fn is_sorted(self) -> bool
is_sorted
#53485)source§fn advance_by(&mut self, n: usize) -> Result<(), NonZeroUsize>
fn advance_by(&mut self, n: usize) -> Result<(), NonZeroUsize>
iter_advance_by
#77404)n
elements. Read moresource§fn next_chunk<const N: usize>(
&mut self
) -> Result<[Self::Item; N], IntoIter<Self::Item, N>>where
Self: Sized,
fn next_chunk<const N: usize>(
&mut self
) -> Result<[Self::Item; N], IntoIter<Self::Item, N>>where
Self: Sized,
iter_next_chunk
#98326)N
values. Read more1.28.0 · source§fn step_by(self, step: usize) -> StepBy<Self> ⓘwhere
Self: Sized,
fn step_by(self, step: usize) -> StepBy<Self> ⓘwhere
Self: Sized,
source§fn chain<U>(self, other: U) -> Chain<Self, U::IntoIter> ⓘ
fn chain<U>(self, other: U) -> Chain<Self, U::IntoIter> ⓘ
source§fn zip<U>(self, other: U) -> Zip<Self, U::IntoIter> ⓘwhere
Self: Sized,
U: IntoIterator,
fn zip<U>(self, other: U) -> Zip<Self, U::IntoIter> ⓘwhere
Self: Sized,
U: IntoIterator,
source§fn intersperse_with<G>(self, separator: G) -> IntersperseWith<Self, G> ⓘ
fn intersperse_with<G>(self, separator: G) -> IntersperseWith<Self, G> ⓘ
iter_intersperse
#79524)separator
between adjacent items of the original iterator. Read moresource§fn map<B, F>(self, f: F) -> Map<Self, F> ⓘ
fn map<B, F>(self, f: F) -> Map<Self, F> ⓘ
source§fn filter<P>(self, predicate: P) -> Filter<Self, P> ⓘ
fn filter<P>(self, predicate: P) -> Filter<Self, P> ⓘ
source§fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F> ⓘ
fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F> ⓘ
source§fn enumerate(self) -> Enumerate<Self> ⓘwhere
Self: Sized,
fn enumerate(self) -> Enumerate<Self> ⓘwhere
Self: Sized,
source§fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P> ⓘ
fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P> ⓘ
source§fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P> ⓘ
fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P> ⓘ
1.57.0 · source§fn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P> ⓘ
fn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P> ⓘ
source§fn skip(self, n: usize) -> Skip<Self> ⓘwhere
Self: Sized,
fn skip(self, n: usize) -> Skip<Self> ⓘwhere
Self: Sized,
n
elements. Read moresource§fn take(self, n: usize) -> Take<Self> ⓘwhere
Self: Sized,
fn take(self, n: usize) -> Take<Self> ⓘwhere
Self: Sized,
n
elements, or fewer
if the underlying iterator ends sooner. Read moresource§fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F> ⓘ
fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F> ⓘ
source§fn map_windows<F, R, const N: usize>(self, f: F) -> MapWindows<Self, F, N> ⓘ
fn map_windows<F, R, const N: usize>(self, f: F) -> MapWindows<Self, F, N> ⓘ
iter_map_windows
#87155)f
for each contiguous window of size N
over
self
and returns an iterator over the outputs of f
. Like slice::windows()
,
the windows during mapping overlap as well. Read moresource§fn inspect<F>(self, f: F) -> Inspect<Self, F> ⓘ
fn inspect<F>(self, f: F) -> Inspect<Self, F> ⓘ
source§fn by_ref(&mut self) -> &mut Selfwhere
Self: Sized,
fn by_ref(&mut self) -> &mut Selfwhere
Self: Sized,
source§fn collect<B: FromIterator<Self::Item>>(self) -> Bwhere
Self: Sized,
fn collect<B: FromIterator<Self::Item>>(self) -> Bwhere
Self: Sized,
source§fn collect_into<E: Extend<Self::Item>>(self, collection: &mut E) -> &mut Ewhere
Self: Sized,
fn collect_into<E: Extend<Self::Item>>(self, collection: &mut E) -> &mut Ewhere
Self: Sized,
iter_collect_into
#94780)source§fn partition<B, F>(self, f: F) -> (B, B)
fn partition<B, F>(self, f: F) -> (B, B)
source§fn partition_in_place<'a, T: 'a, P>(self, predicate: P) -> usize
fn partition_in_place<'a, T: 'a, P>(self, predicate: P) -> usize
iter_partition_in_place
#62543)true
precede all those that return false
.
Returns the number of true
elements found. Read moresource§fn is_partitioned<P>(self, predicate: P) -> bool
fn is_partitioned<P>(self, predicate: P) -> bool
iter_is_partitioned
#62544)true
precede all those that return false
. Read more1.27.0 · source§fn try_fold<B, F, R>(&mut self, init: B, f: F) -> R
fn try_fold<B, F, R>(&mut self, init: B, f: F) -> R
1.27.0 · source§fn try_for_each<F, R>(&mut self, f: F) -> R
fn try_for_each<F, R>(&mut self, f: F) -> R
source§fn fold<B, F>(self, init: B, f: F) -> B
fn fold<B, F>(self, init: B, f: F) -> B
1.51.0 · source§fn reduce<F>(self, f: F) -> Option<Self::Item>
fn reduce<F>(self, f: F) -> Option<Self::Item>
source§fn try_reduce<F, R>(
&mut self,
f: F
) -> <<R as Try>::Residual as Residual<Option<R::Output>>>::TryType
fn try_reduce<F, R>( &mut self, f: F ) -> <<R as Try>::Residual as Residual<Option<R::Output>>>::TryType
iterator_try_reduce
#87053)source§fn all<F>(&mut self, f: F) -> bool
fn all<F>(&mut self, f: F) -> bool
source§fn any<F>(&mut self, f: F) -> bool
fn any<F>(&mut self, f: F) -> bool
source§fn find<P>(&mut self, predicate: P) -> Option<Self::Item>
fn find<P>(&mut self, predicate: P) -> Option<Self::Item>
1.30.0 · source§fn find_map<B, F>(&mut self, f: F) -> Option<B>
fn find_map<B, F>(&mut self, f: F) -> Option<B>
source§fn try_find<F, R>(
&mut self,
f: F
) -> <<R as Try>::Residual as Residual<Option<Self::Item>>>::TryType
fn try_find<F, R>( &mut self, f: F ) -> <<R as Try>::Residual as Residual<Option<Self::Item>>>::TryType
try_find
#63178)source§fn position<P>(&mut self, predicate: P) -> Option<usize>
fn position<P>(&mut self, predicate: P) -> Option<usize>
1.6.0 · source§fn max_by_key<B: Ord, F>(self, f: F) -> Option<Self::Item>
fn max_by_key<B: Ord, F>(self, f: F) -> Option<Self::Item>
1.15.0 · source§fn max_by<F>(self, compare: F) -> Option<Self::Item>
fn max_by<F>(self, compare: F) -> Option<Self::Item>
1.6.0 · source§fn min_by_key<B: Ord, F>(self, f: F) -> Option<Self::Item>
fn min_by_key<B: Ord, F>(self, f: F) -> Option<Self::Item>
1.15.0 · source§fn min_by<F>(self, compare: F) -> Option<Self::Item>
fn min_by<F>(self, compare: F) -> Option<Self::Item>
source§fn rev(self) -> Rev<Self> ⓘwhere
Self: Sized + DoubleEndedIterator,
fn rev(self) -> Rev<Self> ⓘwhere
Self: Sized + DoubleEndedIterator,
source§fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB)
fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB)
1.36.0 · source§fn copied<'a, T>(self) -> Copied<Self> ⓘ
fn copied<'a, T>(self) -> Copied<Self> ⓘ
source§fn array_chunks<const N: usize>(self) -> ArrayChunks<Self, N> ⓘwhere
Self: Sized,
fn array_chunks<const N: usize>(self) -> ArrayChunks<Self, N> ⓘwhere
Self: Sized,
iter_array_chunks
#100450)N
elements of the iterator at a time. Read more1.11.0 · source§fn product<P>(self) -> P
fn product<P>(self) -> P
source§fn cmp_by<I, F>(self, other: I, cmp: F) -> Ordering
fn cmp_by<I, F>(self, other: I, cmp: F) -> Ordering
iter_order_by
#64295)Iterator
with those
of another with respect to the specified comparison function. Read more1.5.0 · source§fn partial_cmp<I>(self, other: I) -> Option<Ordering>
fn partial_cmp<I>(self, other: I) -> Option<Ordering>
PartialOrd
elements of
this Iterator
with those of another. The comparison works like short-circuit
evaluation, returning a result without comparing the remaining elements.
As soon as an order can be determined, the evaluation stops and a result is returned. Read moresource§fn partial_cmp_by<I, F>(self, other: I, partial_cmp: F) -> Option<Ordering>
fn partial_cmp_by<I, F>(self, other: I, partial_cmp: F) -> Option<Ordering>
iter_order_by
#64295)Iterator
with those
of another with respect to the specified comparison function. Read moresource§fn eq_by<I, F>(self, other: I, eq: F) -> bool
fn eq_by<I, F>(self, other: I, eq: F) -> bool
iter_order_by
#64295)1.5.0 · source§fn lt<I>(self, other: I) -> bool
fn lt<I>(self, other: I) -> bool
Iterator
are lexicographically
less than those of another. Read more1.5.0 · source§fn le<I>(self, other: I) -> bool
fn le<I>(self, other: I) -> bool
Iterator
are lexicographically
less or equal to those of another. Read more1.5.0 · source§fn gt<I>(self, other: I) -> bool
fn gt<I>(self, other: I) -> bool
Iterator
are lexicographically
greater than those of another. Read more1.5.0 · source§fn ge<I>(self, other: I) -> bool
fn ge<I>(self, other: I) -> bool
Iterator
are lexicographically
greater than or equal to those of another. Read moresource§fn is_sorted_by<F>(self, compare: F) -> bool
fn is_sorted_by<F>(self, compare: F) -> bool
is_sorted
#53485)1.28.0 · source§impl<T> RangeBounds<T> for Range<&T>
impl<T> RangeBounds<T> for Range<&T>
1.28.0 · source§impl<T> RangeBounds<T> for Range<T>
impl<T> RangeBounds<T> for Range<T>
1.15.0 (const: unstable) · source§impl<T> SliceIndex<[T]> for Range<usize>
impl<T> SliceIndex<[T]> for Range<usize>
const: unstable · source§fn get(self, slice: &[T]) -> Option<&[T]>
fn get(self, slice: &[T]) -> Option<&[T]>
slice_index_methods
)const: unstable · source§fn get_mut(self, slice: &mut [T]) -> Option<&mut [T]>
fn get_mut(self, slice: &mut [T]) -> Option<&mut [T]>
slice_index_methods
)const: unstable · source§unsafe fn get_unchecked(self, slice: *const [T]) -> *const [T]
unsafe fn get_unchecked(self, slice: *const [T]) -> *const [T]
slice_index_methods
)slice
pointer
is undefined behavior even if the resulting reference is not used.const: unstable · source§unsafe fn get_unchecked_mut(self, slice: *mut [T]) -> *mut [T]
unsafe fn get_unchecked_mut(self, slice: *mut [T]) -> *mut [T]
slice_index_methods
)slice
pointer
is undefined behavior even if the resulting reference is not used.1.20.0 (const: unstable) · source§impl SliceIndex<str> for Range<usize>
impl SliceIndex<str> for Range<usize>
Implements substring slicing with syntax &self[begin .. end]
or &mut self[begin .. end]
.
Returns a slice of the given string from the byte range
[begin
, end
).
This operation is O(1).
Prior to 1.20.0, these indexing operations were still supported by
direct implementation of Index
and IndexMut
.
Panics
Panics if begin
or end
does not point to the starting byte offset of
a character (as defined by is_char_boundary
), if begin > end
, or if
end > len
.
Examples
let s = "Löwe 老虎 Léopard";
assert_eq!(&s[0 .. 1], "L");
assert_eq!(&s[1 .. 9], "öwe 老");
// these will panic:
// byte 2 lies within `ö`:
// &s[2 ..3];
// byte 8 lies within `老`
// &s[1 .. 8];
// byte 100 is outside the string
// &s[3 .. 100];
Runconst: unstable · source§fn get(self, slice: &str) -> Option<&Self::Output>
fn get(self, slice: &str) -> Option<&Self::Output>
slice_index_methods
)const: unstable · source§fn get_mut(self, slice: &mut str) -> Option<&mut Self::Output>
fn get_mut(self, slice: &mut str) -> Option<&mut Self::Output>
slice_index_methods
)const: unstable · source§unsafe fn get_unchecked(self, slice: *const str) -> *const Self::Output
unsafe fn get_unchecked(self, slice: *const str) -> *const Self::Output
slice_index_methods
)slice
pointer
is undefined behavior even if the resulting reference is not used.const: unstable · source§unsafe fn get_unchecked_mut(self, slice: *mut str) -> *mut Self::Output
unsafe fn get_unchecked_mut(self, slice: *mut str) -> *mut Self::Output
slice_index_methods
)slice
pointer
is undefined behavior even if the resulting reference is not used.