fn open_slot(&self) -> Option<usize> {
		assert!(self.is_leaf());
		let slot = self.empty_slot();
		if let Some(s) = slot {
			if s < 7 {
				return slot;
			}
		}
		None
	}
/// Find the first open child slot in a leaf
Find the first open child slot in a leaf
Find the first open child slot in a leaf
fn open_slot(&self) -> Option<usize> {
		assert!(self.is_leaf());
		let slot = self.empty_slot();
		if let Some(s) = slot {
			if s < 7 {
				return slot;
			}
		}
		None
	}
fn open_slot ( & self ) -> Option < usize > { assert ! ( self is_leaf ( ) ) ; let slot = self . empty_slot ( ) ; if let Some ( s ) = slot { if s < 7 { return slot ; } } None }
Find the first open child slot in a leaf
Find the first open child slot in a leaf
&self