Struct Engine 

pub struct Engine { /* private fields */ }

Engine for evaluating Lemma rules.

Pure Rust implementation that evaluates Lemma specs directly from the AST. Uses pre-built execution plans that are self-contained and ready for evaluation.

The engine never performs network calls. External @... references must be pre-resolved before loading — either by including dependency sources in the source map or by calling resolve_registry_references separately (e.g. in a lemma fetch command).

Implementations

impl Engine

pub fn new() -> Self

pub fn with_limits(limits: ResourceLimits) -> Self

pub fn limits(&self) -> &ResourceLimits

Resource limits configured for this engine.

pub fn load( &mut self, sources: impl IntoIterator<Item = (SourceType, impl Into<String>)>, ) -> Result<(), Errors>

Load Lemma sources in one planning pass. Pairs are (source_type, source_text).

Provenance is derived solely from SourceType: SourceType::Path and SourceType::Volatile are workspace-local; SourceType::Dependency tags repositories with that dependency id.

pub fn list(&self) -> Vec<ResolvedRepository>

Every loaded repository in insertion order (workspace, embedded stdlib EMBEDDED_STDLIB_REPOSITORY, dependencies).

Returns listed spec rows (metadata only, no AST, no source text).

pub fn show( &self, repository: Option<&str>, spec: &str, effective: Option<&DateTimeValue>, ) -> Result<Show, Error>

Spec interface and resolved temporal window at effective.

Show.data lists only data used by the spec’s rules. Lemma source text is Self::source.

pub fn source( &self, repository: Option<&str>, spec: Option<&str>, effective: Option<&DateTimeValue>, ) -> Result<String, Error>

Formatted canonical Lemma source for a repository or one spec slice.

When spec is None, returns all specs in the repository sorted by name/effective. When spec is Some, effective selects the temporal slice (default: now).

pub fn run( &self, repository: Option<&str>, spec: &str, effective: Option<&DateTimeValue>, data: HashMap<String, String>, rules: Option<&[String]>, explain: bool, ) -> Result<Response, Error>

Evaluate a spec.

pub fn remove( &mut self, repository: Option<&str>, spec: &str, effective: Option<&DateTimeValue>, ) -> Result<(), Error>

Trait Implementations

impl Default for Engine

fn default() -> Self

Returns the “default value” for a type.