Struct Filter 

pub struct Filter {
    pub session_id: Option<String>,
    pub terms: Vec<FilterTerm>,
}

Pre-scoring filter applied by crate::Mnemo::recall (Phase 12.6).

session_id restricts candidates to a single session (when the memory’s session_id is set). The terms are AND-ed metadata conditions evaluated against each candidate’s metadata map; see FilterTerm for the shapes.

When an ANN index is present, the filter is applied after the ANN shortlist step, so a selective filter can starve the result below top_k. Recall handles that automatically via the Phase 12.1 short-results-on-indexed-path fix (widen 2×, then exact scan).

Fields

session_id: Option<String>

Only candidates whose Memory.session_id equals this value. Candidates without a session_id are excluded when this is set.

terms: Vec<FilterTerm>

AND-ed metadata conditions. Empty → no metadata constraints.

Implementations

impl Filter

pub fn new_session(session: impl Into<String>) -> Self

Builder helper: a filter that keeps only memories in session.

pub fn with_session(self, session: impl Into<String>) -> Self

Restrict to one session_id (builder form).

pub fn metadata_exists(self, key: impl Into<String>) -> Self

Require metadata[key] to exist (any value).

pub fn metadata_eq(self, key: impl Into<String>, value: Value) -> Self

Require metadata[key] to equal value.

pub fn metadata_in(self, key: impl Into<String>, values: Vec<Value>) -> Self

Require metadata[key] to be one of values.

pub fn metadata_range( self, key: impl Into<String>, min: Option<f64>, max: Option<f64>, ) -> Self

Require metadata[key] to be a number in [min, max].

pub fn is_empty(&self) -> bool

true iff the filter has no terms and no session_id. The recall hot path uses this to skip the per-candidate filter check entirely.

pub fn matches(&self, m: &Memory) -> bool

Evaluate the filter against one memory. Returns true if the memory passes every term.

Trait Implementations

impl Clone for Filter

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Filter

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

Formats the value using the given formatter.

impl Default for Filter

fn default() -> Self

Returns the “default value” for a type.