Trait WeightElement 

pub trait WeightElement:
    Clone
    + Default
    + 'static {
    type Sum: NumericSize;

    const IS_UNIT: bool;

    // Required methods
    fn unit() -> Self;
    fn validate_element(&self, context: &str) -> Result<(), ConstructionError>;
    fn to_sum(&self) -> Self::Sum;

    // Provided methods
    fn checked_add_to_sum(
        total: Self::Sum,
        value: Self::Sum,
        context: &str,
    ) -> Result<Self::Sum, EvaluationError> { ... }
    fn checked_mul_sum(
        left: Self::Sum,
        right: Self::Sum,
        context: &str,
    ) -> Result<Self::Sum, EvaluationError> { ... }
}

Maps a weight element to its sum/metric type.

This decouples the per-element weight type from the accumulation type. Exact integer weights use a wider accumulation type: i64 and the unit weight One both use i64. Approximate f64 weights continue to sum into f64.

Required Associated Constants

const IS_UNIT: bool

Whether this is the unit weight type (One).

Required Associated Types

type Sum: NumericSize

The numeric type used for sums and comparisons.

Required Methods

fn unit() -> Self

Construct the multiplicative unit weight.

fn validate_element(&self, context: &str) -> Result<(), ConstructionError>

Validate that an element belongs to the public weight domain.

fn to_sum(&self) -> Self::Sum

Convert this weight element to the sum type.

Provided Methods

fn checked_add_to_sum( total: Self::Sum, value: Self::Sum, context: &str, ) -> Result<Self::Sum, EvaluationError>

Add one element to an evaluated objective without overflowing or producing a non-finite value.

fn checked_mul_sum( left: Self::Sum, right: Self::Sum, context: &str, ) -> Result<Self::Sum, EvaluationError>

Multiply evaluated quantities without overflowing or producing a non-finite value.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementations on Foreign Types

impl WeightElement for f64

const IS_UNIT: bool = false

type Sum = f64

fn unit() -> Self

fn validate_element(&self, context: &str) -> Result<(), ConstructionError>

fn to_sum(&self) -> f64

impl WeightElement for i64

const IS_UNIT: bool = false

type Sum = i64

fn unit() -> Self

fn validate_element(&self, _context: &str) -> Result<(), ConstructionError>

fn to_sum(&self) -> i64

Implementors

impl WeightElement for One

const IS_UNIT: bool = true

type Sum = i64