Struct Position 

pub struct Position {
    pub group: u64,
    pub frame: u64,
}

A frame-precise point in a track: a group sequence and a frame index within it.

Ordered lexicographically, so comparing positions is the same as comparing groups and only falling back to frames within one. This is the model’s counterpart of the wire’s (Group, Frame) pairs on SUBSCRIBE and FETCH.

Pairing the two is the point: a frame index counts from the start of a group, so it means nothing on its own. Carrying them together makes “frame 5 of nothing” unrepresentable rather than merely undefined.

Fields

group: u64

The group sequence.

frame: u64

The frame index within the group, numbered from 0 in write order.

Implementations

impl Position

pub fn group(group: u64) -> Self

The first frame of group.

As an exclusive end this means “everything before group”; as a start it means “group from the beginning”.

pub fn after(group: u64, frame: u64) -> Option<Self>

The position just past frame of group: the exclusive end that includes it.

None when there is no such position, i.e. the very last frame of the very last group. That is past everything, which Subscription::end spells None too, so the two meanings line up and with_end can take this directly.

pub fn after_group(group: u64) -> Option<Self>

The position just past every frame of group: the exclusive end that includes the group whole.

None past the last group, for the reason given on Self::after.

pub fn group_end(self) -> Bound<u64>

The bound this exclusive end puts on a group cursor, for crate::track::Subscriber::set_groups.

A head-of-group end excludes its group. A mid-group end includes it, so a frame cap can apply within that group.

Trait Implementations

impl Clone for Position

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for Position

impl Debug for Position

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Position

fn default() -> Self

Returns the “default value” for a type.

impl Eq for Position

impl Ord for Position

fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

fn clamp_to<R>(self, range: R) -> Self

where Self: Sized, R: ClampBounds<Self>,

🔬This is a nightly-only experimental API. (clamp_to)

Restrict a value to a certain range.

impl PartialEq for Position

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl PartialOrd for Position

fn partial_cmp(&self, other: &Self) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl StructuralPartialEq for Position