Struct Program 

pub struct Program<'p> {
    pub arena: &'p Arena,
    pub ext_preds: Vec<PredicateIndex>,
    pub rules: FxHashMap<PredicateIndex, Vec<&'p Clause<'p>>>,
}

Represents a Mangle program consisting of logic rules and declarations.

Program wraps the AST and provides the necessary methods to identify predicates and their dependencies. It is the primary input for the stratification algorithm.

It distinguishes between extensional predicates (stored facts) and intensional predicates (derived rules).

Fields

arena: &'p Arena

ext_preds: Vec<PredicateIndex>

rules: FxHashMap<PredicateIndex, Vec<&'p Clause<'p>>>

Implementations

impl<'p> Program<'p>

pub fn new(arena: &'p Arena) -> Self

pub fn add_clause<'src>(&mut self, src: &'src Arena, clause: &'src Clause<'_>)

pub fn arena(&'p self) -> &'p Arena

Returns the AST Arena containing the program data.

pub fn extensional_preds(&'p self) -> PredicateSet

Returns predicates for extensional DB (stored facts).

pub fn intensional_preds(&'p self) -> PredicateSet

Returns predicates for intensional DB (derived rules).

pub fn rules( &'p self, sym: PredicateIndex, ) -> impl Iterator<Item = &'p Clause<'p>>

Maps predicates of intensional DB to their defining rules.

pub fn stratify(self) -> Result<StratifiedProgram<'p>, String>

Analyzes the program’s dependency graph and attempts to stratify it.

Stratification partitions the predicates into ordered layers (strata). This is essential for evaluating programs with negation or aggregation, ensuring that dependencies are fully evaluated before they are used.

Returns a StratifiedProgram on success, or an error if the program contains unstratifiable cycles (e.g., negation cycles).

Trait Implementations

impl<'p> Clone for Program<'p>

fn clone(&self) -> Program<'p>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'p> Debug for Program<'p>

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

Formats the value using the given formatter.