/// Returns the [`FieldSet`] that describes what parts of each tuple should
/// be considered.
///
/// Each `T` tuple may have more fields than `significant_fields`. However,
/// comparisons should only use `significant_fields` in order to compare
/// sub-parts of different vectors to see if they should be joined.
Returns the [`FieldSet`] that describes what parts of each tuple should
be considered.

Each `T` tuple may have more fields than `significant_fields`. However,
comparisons should only use `significant_fields` in order to compare
sub-parts of different vectors to see if they should be joined.
Returns the [ ` FieldSet ` ] that describes what parts of each tuple should be considered . Each ` T ` tuple may have more fields than ` significant_fields ` . However comparisons should only use ` significant_fields ` in order to compare sub - parts of different vectors to see if they should be joined .
fn significant_fields(&self) -> &T::FieldSet {
        // SAFETY: `HashJoinKey` only ever lives in `HashJoin`, which
        // ensures that `significant_fields` is allocated in a box and never
        // moved or mutated during its lifetime.
        unsafe { self.significant_fields.as_ref() }
    }
fn significant_fields ( & self ) -> & T :: FieldSet { // SAFETY: `HashJoinKey` only ever lives in `HashJoin`, which // ensures that `significant_fields` is allocated in a box and never // moved or mutated during its lifetime. unsafe { self . significant_fields . as_ref ( ) } }
Returns the [`FieldSet`] that describes what parts of each tuple should
be considered.
Returns the [ ` FieldSet ` ] that describes what parts of each tuple should be considered .
&self