pub struct RangeTo<Idx> {
pub end: Idx,
}
new_range_api
)Expand description
A range only bounded exclusively above (..end
).
The RangeTo
..end
contains all values with x < end
.
It cannot serve as an Iterator
because it doesn’t have a starting point.
§Examples
The ..end
syntax is a RangeTo
:
assert_eq!((..5), std::ops::RangeTo { end: 5 });
It does not have an IntoIterator
implementation, so you can’t use it in
a for
loop directly. This won’t compile:
// error[E0277]: the trait bound `std::ops::RangeTo<{integer}>:
// std::iter::Iterator` is not satisfied
for i in ..5 {
// ...
}
When used as a slicing index, RangeTo
produces a slice of all array
elements before the index indicated by end
.
let arr = [0, 1, 2, 3, 4];
assert_eq!(arr[ .. ], [0, 1, 2, 3, 4]);
assert_eq!(arr[ .. 3], [0, 1, 2 ]); // This is a `RangeTo`
assert_eq!(arr[ ..=3], [0, 1, 2, 3 ]);
assert_eq!(arr[1.. ], [ 1, 2, 3, 4]);
assert_eq!(arr[1.. 3], [ 1, 2 ]);
assert_eq!(arr[1..=3], [ 1, 2, 3 ]);
Fields§
§end: Idx
new_range_api
)The upper bound of the range (exclusive).
Implementations§
source§impl<Idx> RangeTo<Idx>where
Idx: PartialOrd,
impl<Idx> RangeTo<Idx>where
Idx: PartialOrd,
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!( (..5).contains(&-1_000_000_000));
assert!( (..5).contains(&4));
assert!(!(..5).contains(&5));
assert!( (..1.0).contains(&0.5));
assert!(!(..1.0).contains(&f32::NAN));
assert!(!(..f32::NAN).contains(&0.5));
Trait Implementations§
§impl<'a, A> Arbitrary<'a> for RangeTo<A>where
A: Arbitrary<'a> + Clone + PartialOrd,
impl<'a, A> Arbitrary<'a> for RangeTo<A>where
A: Arbitrary<'a> + Clone + PartialOrd,
§fn arbitrary(u: &mut Unstructured<'a>) -> Result<RangeTo<A>, Error>
fn arbitrary(u: &mut Unstructured<'a>) -> Result<RangeTo<A>, Error>
Self
from the given unstructured data. Read more§fn size_hint(depth: usize) -> (usize, Option<usize>)
fn size_hint(depth: usize) -> (usize, Option<usize>)
Unstructured
this type
needs to construct itself. Read more§fn arbitrary_take_rest(u: Unstructured<'a>) -> Result<Self, Error>
fn arbitrary_take_rest(u: Unstructured<'a>) -> Result<Self, Error>
Self
from the entirety of the given
unstructured data. Read moresource§impl<'de, Idx> Deserialize<'de> for RangeTo<Idx>where
Idx: Deserialize<'de>,
impl<'de, Idx> Deserialize<'de> for RangeTo<Idx>where
Idx: Deserialize<'de>,
source§fn deserialize<D>(
deserializer: D,
) -> Result<RangeTo<Idx>, <D as Deserializer<'de>>::Error>where
D: Deserializer<'de>,
fn deserialize<D>(
deserializer: D,
) -> Result<RangeTo<Idx>, <D as Deserializer<'de>>::Error>where
D: Deserializer<'de>,
1.28.0 · source§impl<T> RangeBounds<T> for RangeTo<&T>
impl<T> RangeBounds<T> for RangeTo<&T>
1.28.0 · source§impl<T> RangeBounds<T> for RangeTo<T>
impl<T> RangeBounds<T> for RangeTo<T>
source§impl<Idx> Serialize for RangeTo<Idx>where
Idx: Serialize,
impl<Idx> Serialize for RangeTo<Idx>where
Idx: Serialize,
source§fn serialize<S>(
&self,
serializer: S,
) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>where
S: Serializer,
fn serialize<S>(
&self,
serializer: S,
) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>where
S: Serializer,
1.15.0 · source§impl<T> SliceIndex<[T]> for RangeTo<usize>
impl<T> SliceIndex<[T]> for RangeTo<usize>
The methods index
and index_mut
panic if the end of the range is out of bounds.
source§fn get(self, slice: &[T]) -> Option<&[T]>
fn get(self, slice: &[T]) -> Option<&[T]>
slice_index_methods
)source§fn get_mut(self, slice: &mut [T]) -> Option<&mut [T]>
fn get_mut(self, slice: &mut [T]) -> Option<&mut [T]>
slice_index_methods
)source§unsafe fn get_unchecked(self, slice: *const [T]) -> *const [T]
unsafe fn get_unchecked(self, slice: *const [T]) -> *const [T]
slice_index_methods
)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
)1.20.0 · source§impl SliceIndex<str> for RangeTo<usize>
impl SliceIndex<str> for RangeTo<usize>
Implements substring slicing with syntax &self[.. end]
or &mut self[.. end]
.
Returns a slice of the given string from the byte range [0, end
).
Equivalent to &self[0 .. end]
or &mut self[0 .. 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 end
does not point to the starting byte offset of a
character (as defined by is_char_boundary
), or if end > len
.
source§fn get(
self,
slice: &str,
) -> Option<&<RangeTo<usize> as SliceIndex<str>>::Output>
fn get( self, slice: &str, ) -> Option<&<RangeTo<usize> as SliceIndex<str>>::Output>
slice_index_methods
)source§fn get_mut(
self,
slice: &mut str,
) -> Option<&mut <RangeTo<usize> as SliceIndex<str>>::Output>
fn get_mut( self, slice: &mut str, ) -> Option<&mut <RangeTo<usize> as SliceIndex<str>>::Output>
slice_index_methods
)source§unsafe fn get_unchecked(
self,
slice: *const str,
) -> *const <RangeTo<usize> as SliceIndex<str>>::Output
unsafe fn get_unchecked( self, slice: *const str, ) -> *const <RangeTo<usize> as SliceIndex<str>>::Output
slice_index_methods
)source§unsafe fn get_unchecked_mut(
self,
slice: *mut str,
) -> *mut <RangeTo<usize> as SliceIndex<str>>::Output
unsafe fn get_unchecked_mut( self, slice: *mut str, ) -> *mut <RangeTo<usize> as SliceIndex<str>>::Output
slice_index_methods
)impl<Idx> Copy for RangeTo<Idx>where
Idx: Copy,
impl<Idx> Eq for RangeTo<Idx>where
Idx: Eq,
impl<T> OneSidedRange<T> for RangeTo<T>where
RangeTo<T>: RangeBounds<T>,
impl<Idx> StructuralPartialEq for RangeTo<Idx>
Auto Trait Implementations§
impl<Idx> Freeze for RangeTo<Idx>where
Idx: Freeze,
impl<Idx> RefUnwindSafe for RangeTo<Idx>where
Idx: RefUnwindSafe,
impl<Idx> Send for RangeTo<Idx>where
Idx: Send,
impl<Idx> Sync for RangeTo<Idx>where
Idx: Sync,
impl<Idx> Unpin for RangeTo<Idx>where
Idx: Unpin,
impl<Idx> UnwindSafe for RangeTo<Idx>where
Idx: 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§unsafe fn clone_to_uninit(&self, dst: *mut T)
unsafe fn clone_to_uninit(&self, dst: *mut T)
clone_to_uninit
)§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key
and return true
if they are equal.