Function shorthand_label_predicate

graphlite/src/ast/parser.rs:1653–1678

Parse shorthand label predicate: identifier:label (e.g., n:Person)

(tokens: &[Token])

/// Parse shorthand label predicate: identifier:label (e.g., n:Person)
fn shorthand_label_predicate(tokens: &[Token]) -> IResult<&[Token], Expression> {
    map(
        tuple((identifier, expect_token(Token::Colon), identifier)),
        |(var_name, _, label_name)| {
            let label_expr = LabelExpression {
                terms: vec![LabelTerm {
                    factors: vec![LabelFactor::Identifier(label_name)],
                    location: Location::default(),
                }],
                location: Location::default(),
            };

            Expression::IsPredicate(IsPredicateExpression {
                subject: Box::new(Expression::Variable(Variable {
                    name: var_name,
                    location: Location::default(),
                })),
                predicate_type: IsPredicateType::Label(label_expr),
                negated: false,
                target: None,
                type_spec: None,
                location: Location::default(),
            })
        },
    )(tokens)
}

/// Parse comparison: expr op expr | expr IN (subquery) | expr IN (list) | expr NOT IN (subquery) | expr NOT IN (list) | expr IS [NOT] predicate
fn comparison(tokens: &[Token]) -> IResult<&[Token], Expression> {