Struct Span 

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

A byte-offset span into the original source buffer. Never owns data; always references the original input.

Fields

start: usize

end: usize

Implementations

impl Span

pub fn new(start: usize, end: usize) -> Span

Construct a span. Panics in both debug and release builds if start > end, because such a span will inevitably panic later at slice time and the early panic gives a better error message.

pub fn len(&self) -> usize

pub fn is_empty(&self) -> bool

pub fn as_slice<'a>(&self, source: &'a [u8]) -> &'a [u8]

Borrow the span’s bytes from source. Panics if the span is out of bounds for source — use Span::try_as_slice when the caller cannot guarantee bounds.

pub fn try_as_slice<'a>(&self, source: &'a [u8]) -> Option<&'a [u8]>

Borrow the span’s bytes from source, returning None if the span lies outside the buffer instead of panicking.

pub fn as_str<'a>(&self, source: &'a [u8]) -> Result<&'a str, Utf8Error>

Extract the spanned bytes as a UTF-8 string slice.

Returns Err if the span does not cover valid UTF-8. Callers that know the source is ASCII can use .unwrap() in tests or .expect("...") with context.

Trait Implementations

impl Clone for Span

fn clone(&self) -> Span

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Span

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

Formats the value using the given formatter.

impl Hash for Span

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

where __H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for Span

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

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for Span

impl Eq for Span

impl StructuralPartialEq for Span