Struct TrigramQuery 

pub struct TrigramQuery {
    pub dnfs: Vec<TrigramDnf>,
}

A boolean query over trigrams: a conjunction of DNFs. A document is a candidate when it satisfies every DNF, where a DNF is satisfied when at least one of its AND-groups is fully present in the document.

This one shape expresses everything the planner produces:

• an exact literal is one DNF with a single AND-group (all its trigrams);
• a case-insensitive literal contributes one DNF per needle window, each a disjunction of single-trigram groups (the window’s fold variants);
• a regex contributes a DNF for its required prefix literals and another for its required suffix literals.

A DNF that cannot filter (it is empty, or contains an empty group, which would make it trivially true) is ignored. An empty query means “scan everything”.

Fields

dnfs: Vec<TrigramDnf>

Implementations

impl TrigramQuery

pub fn is_unconstrained(&self) -> bool

True when no usable trigram constraints exist and all documents are candidates.

pub fn from_literal(needle: &[u8]) -> TrigramQuery

pub fn from_literal_ci(needle: &[u8]) -> TrigramQuery

Build a case-insensitive literal query. Each 3-byte window of the needle becomes one DNF listing every byte sequence the window can begin with in a match, so the trigram index can still prune candidates without false negatives.

The matcher folds case Unicode-aware, so a window’s variants are not just its ASCII case permutations: s/S also matches U+017F (LATIN SMALL LETTER LONG S) and k/K also matches U+212A (KELVIN SIGN), whose UTF-8 encodings are multi-byte. For each window we enumerate every combination of per-character fold forms and take the first three bytes of each — exactly the set of trigrams a match of that window can start with. Windows containing non-ASCII needle bytes are skipped (their fold forms aren’t enumerable this way), which only widens the candidate set.

Trait Implementations

impl Clone for TrigramQuery

fn clone(&self) -> TrigramQuery

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for TrigramQuery

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

Formats the value using the given formatter.

impl Default for TrigramQuery

fn default() -> TrigramQuery

Returns the “default value” for a type.