Struct VerLink

pub struct VerLink { /* private fields */ }

A linked list tracking a logic “version” with compatibility rules:

• Append-only changes bump the version, the new version is backwards compatible.
• Non-append-only changes create a new version that is incompatible with all other versions (in the current process).
• Clones (cheaply) preserve the version.

Supported operations:

• new() -> x: Create a new version that is not comparable (compatible) with other versions.
• clone(x) -> y: Clone x to y. x == y. x and y are compatible.
• bump(x) -> y: Bump x to y. y > x. y is backwards-compatible with x. Note: y is not comparable (compatible) with other bump(x).
• x > y: true if x is backwards compatible with y.

The linked list can be shared in other linked lists. So they form a tree effectively. Comparing to a DAG, there is no “merge” operation. Compatibility questions become reachability questions.

Implementations

impl VerLink

pub fn new() -> Self

Creates a new VerLink that is incompatible with all other VerLinks in the process.

pub fn bump(&mut self)

Bumps the VerLink for backward-compatible (ex. append-only) changes.

Trait Implementations

impl Clone for VerLink

fn clone(&self) -> VerLink

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for VerLink

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

Formats the value using the given formatter.

impl<'a> From<&'a VerLink> for DagVersion<'a>

fn from(version: &'a VerLink) -> Self

Converts to this type from the input type.

impl<'a> From<&'a VerLink> for IdMapVersion<'a>

fn from(version: &'a VerLink) -> Self

Converts to this type from the input type.

impl PartialEq for VerLink

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for VerLink

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.