Struct Goal 

pub struct Goal {
    pub pattern: String,
    pub expression: Option<Expression>,
    pub status: GoalStatus,
    pub sub_goals: Vec<Goal>,
    pub candidate_rules: Vec<String>,
    pub bindings: Bindings,
    pub depth: usize,
}

Represents a goal to prove/achieve in backward chaining

Fields

pattern: String

Target pattern to prove (e.g., “User.IsVIP == true”)

expression: Option<Expression>

Parsed expression AST (if available)

status: GoalStatus

Current status of this goal

sub_goals: Vec<Goal>

Sub-goals that need to be proven first

candidate_rules: Vec<String>

Rules that can potentially derive this goal

bindings: Bindings

Variable bindings accumulated during proof

depth: usize

Depth of this goal in the search tree

Implementations

impl Goal

pub fn new(pattern: String) -> Self

Create a new goal with the given pattern

pub fn with_expression(pattern: String, expression: Expression) -> Self

Create a new goal with parsed expression

pub fn is_proven(&self) -> bool

Check if this goal is proven

pub fn is_unprovable(&self) -> bool

Check if this goal is unprovable

pub fn all_subgoals_proven(&self) -> bool

Check if all sub-goals are proven

pub fn add_subgoal(&mut self, goal: Goal)

Add a sub-goal

pub fn add_candidate_rule(&mut self, rule_name: String)

Add a candidate rule that can derive this goal

Trait Implementations

impl Clone for Goal

fn clone(&self) -> Goal

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Goal

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

Formats the value using the given formatter.