Struct `Span`

pub struct Span { pub start: usize, pub end: usize }

A representation of a range in a haystack.

A span corresponds to the starting and ending byte offsets of a contiguous region of bytes. The starting offset is inclusive while the ending offset is exclusive. That is, a span is a half-open interval.

A span is used to report the offsets of a match, but it is also used to convey which region of a haystack should be searched via routines like Input::span.

This is basically equivalent to a std::ops::Range<usize>, except this type implements Copy which makes it more ergonomic to use in the context of this crate. Indeed, Span exists only because Range<usize> does not implement Copy. Like a range, this implements Index for [u8] and str, and IndexMut for [u8]. For convenience, this also impls From<Range>, which means things like Span::from(5..10) work.

There are no constraints on the values of a span. It is, for example, legal to create a span where start > end.

Fields

start: usize: The start offset of the span, inclusive.
end: usize: The end offset of the span, exclusive.

Implementations

`impl Span`

fn range(&self) -> Range<usize>

Returns this span as a range.

fn is_empty(&self) -> bool

Returns true when this span is empty. That is, when start >= end.

fn len(&self) -> usize

Returns the length of this span.

This returns 0 in precisely the cases that is_empty returns true.

fn contains(&self, offset: usize) -> bool

Returns true when the given offset is contained within this span.

Note that an empty span contains no offsets and will always return false.

fn offset(&self, offset: usize) -> Span

Returns a new span with offset added to this span's start and end values.

Panics

This panics if adding offset to either part of this Span would result in overflow.

Trait Implementations

`impl Clone for Span`

fn clone(&self) -> Self

`impl Copy for Span`

`impl Debug for Span`

fn fmt(&self, f: &mut Formatter<'_>) -> Result

`impl Eq for Span`

`impl From<Range<usize>> for Span`

fn from(range: Range<usize>) -> Span

`impl Hash for Span`

fn hash<__H: Hasher>(&self, state: &mut __H)

`impl PartialEq for Span`

fn eq(&self, other: &Self) -> bool

`impl PartialEq<Range<usize>> for Span`

fn eq(&self, range: &Range<usize>) -> bool

`impl StructuralPartialEq for Span`

Auto Trait Implementations

`impl Freeze for Span`

`impl RefUnwindSafe for Span`

`impl Send for Span`

`impl Sync for Span`

`impl Unpin for Span`

`impl UnsafeUnpin for Span`

`impl UnwindSafe for Span`

Blanket Implementations

`impl<T> Any for Span where T: 'static + ?Sized,`

fn type_id(&self) -> TypeId

`impl<T> Borrow<T> for Span where T: ?Sized,`

fn borrow(&self) -> &T

`impl<T> BorrowMut<T> for Span where T: ?Sized,`

fn borrow_mut(&mut self) -> &mut T

`impl<T> CloneToUninit for Span where T: Clone,`

unsafe fn clone_to_uninit(&self, dest: *mut u8)

`impl<T> From<T> for Span`

fn from(t: T) -> T: Returns the argument unchanged.

`impl<T> ToOwned for Span where T: Clone,`

type Owned = T;
fn to_owned(&self) -> T
fn clone_into(&self, target: &mut T)

`impl<T, U> Into for Span where U: From<T>,`

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of [From]<T> for U chooses to do.

`impl<T, U> TryFrom for Span where U: Into<T>,`

type Error = never;
fn try_from(value: U) -> Result<T, never>

`impl<T, U> TryInto for Span where U: TryFrom<T>,`

type Error = >::Error;
fn try_into(self) -> Result<U, >::Error>