Function extract_float

nodedb-sql/src/planner/select/helpers.rs:167–186

(expr: &ast::Expr)

}

pub fn extract_float(expr: &ast::Expr) -> Result<f64> {
    match expr {
        ast::Expr::Value(v) => match &v.value {
            ast::Value::Number(n, _) => n.parse::<f64>().map_err(|_| SqlError::TypeMismatch {
                detail: format!("expected number: {n}"),
            }),
            _ => Err(SqlError::TypeMismatch {
                detail: format!("expected number, got: {expr}"),
            }),
        },
        // Handle negative numbers: -73.9855 is parsed as UnaryOp { Minus, 73.9855 }
        ast::Expr::UnaryOp {
            op: ast::UnaryOperator::Minus,
            expr: inner,
        } => extract_float(inner).map(|f| -f),
        _ => Err(SqlError::TypeMismatch {
            detail: format!("expected number, got: {expr}"),
        }),
    }
}

/// Map a vector distance function name to its `DistanceMetric`.
///