Function postgis_diesel::operators::overlaps_or_left

pub fn overlaps_or_left<T, U>(
    left: T,
    right: U
) -> BBOverlapsOrLeft<T, U::Expression>where
    T: Expression,
    <T as Expression>::SqlType: SqlType,
    U: AsExpression<T::SqlType>,

The &< operator returns TRUE if the bounding box of geometry A overlaps or is to the left of the bounding box of geometry B, or more accurately, overlaps or is NOT to the right of the bounding box of geometry B.