Struct Ledger 

pub struct Ledger(/* private fields */);

What a process claims to be holding, by quantity name, in SI base units.

A BTreeMap rather than a Vec or a HashMap: names must come out in one order for the audit report to be reproducible, and a hash map’s order is not one order.

Implementations

impl Ledger

pub fn new() -> Ledger

An empty ledger, holding nothing.

pub fn with(self, quantity: &'static str, si_total: f64) -> Ledger

Record a total. Repeating a name adds to it, since a domain made of parts reports the sum of its parts.

pub fn add(&mut self, quantity: &'static str, si_total: f64)

Add to a quantity’s total, in SI base units.

Also raises that entry’s scale to the largest contribution seen, which is what makes a relative tolerance mean anything when the net total is near zero.

pub fn get(&self, quantity: &str) -> Option<f64>

The net total for a quantity.

pub fn scale_of(&self, quantity: &str) -> Option<f64>

The largest single entry that went into a quantity — the scale on which rounding error in its total should be judged.

pub fn is_empty(&self) -> bool

Whether anything at all has been recorded.

pub fn quantities(&self) -> impl Iterator<Item = (&'static str, f64)> + '_

Names and net totals, in a fixed order.

pub fn merged(self, other: &Ledger) -> Ledger

Sum of two ledgers — how a simulation totals its domains. The scales carry over as the larger of the two, so a big domain’s rounding budget is not shrunk by being added to a small one.

Trait Implementations

impl Clone for Ledger

fn clone(&self) -> Ledger

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Ledger

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

Formats the value using the given formatter.

impl Default for Ledger

fn default() -> Ledger

Returns the “default value” for a type.

impl PartialEq for Ledger

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Ledger