Struct Beginning 

pub struct Beginning;

Trait Implementations

impl Debug for Beginning

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

Formats the value using the given formatter.

impl Default for Beginning

fn default() -> Beginning

Returns the “default value” for a type.

impl<I: HaystackItem> Matcher<I> for Beginning

fn matches<'a, H: HaystackOf<'a, I>>(hay: &mut H) -> bool

Checks if the start of the haystack contains a match for this Matcher. If this method successfully matches the start of the haystack, hay is progressed so that hay.item() hasn’t been matched yet. On a fail, the state of hay is undefined.

fn all_matches<'a, H: HaystackOf<'a, I>>(hay: &mut H) -> Vec<usize>

Produces a Vec of all valid haystack states produced as the result of a valid match at the start of hay, used to implement backtracking. The Vec is produced in reverse priority order, so the last match has the highest priority. After calling all_matches, the state of hay itself is undefined.

fn captures<'a, H: HaystackOf<'a, I>>( hay: &mut H, caps: &mut IndexedCaptures, ) -> bool

Checks if the start of the haystack contains a match for this Matcher, writing any groups to caps. Similar to matches, this method progresses hay and caps on a success. On a fail, they have undefined states.

fn all_captures<'a, H: HaystackOf<'a, I>>( hay: &mut H, caps: &mut IndexedCaptures, ) -> Vec<(usize, IndexedCaptures)>

Produces a Vec of all valid captures (and accompanying haystack states) present at the start of hay. Used to implement backtracking for capturing methods. As with all_matches, the resulting Vec is produced in reverse priority order. After calling all_captures, the state of hay and caps are undefined.