Struct ReductionOverhead 

pub struct ReductionOverhead {
    pub output_size: Vec<(&'static str, Expr)>,
}

Overhead specification for a reduction.

Fields

output_size: Vec<(&'static str, Expr)>

Output size as expressions of input size variables. Each entry is (output_field_name, expression).

Implementations

impl ReductionOverhead

pub fn new(output_size: Vec<(&'static str, Expr)>) -> Self

pub fn identity(fields: &[&'static str]) -> Self

Identity overhead: each output field equals the same-named input field. Used by variant cast reductions where problem size doesn’t change.

pub fn evaluate_output_size(&self, input: &ProblemSize) -> ProblemSize

Evaluate output size given input size.

Uses round() for the f64 to usize conversion because expression values are typically integers and any fractional results come from floating-point arithmetic imprecision, not intentional fractions.

pub fn input_variable_names(&self) -> HashSet<&'static str>

Collect all input variable names referenced by the overhead expressions.

pub fn compose(&self, next: &ReductionOverhead) -> ReductionOverhead

Compose two overheads: substitute self’s output into next’s input.

Returns a new overhead whose expressions map from self’s input variables directly to next’s output variables.

pub fn get(&self, name: &str) -> Option<&Expr>

Get the expression for a named output field.

Trait Implementations

impl Clone for ReductionOverhead

fn clone(&self) -> ReductionOverhead

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ReductionOverhead

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

Formats the value using the given formatter.

impl Default for ReductionOverhead

fn default() -> ReductionOverhead

Returns the “default value” for a type.

impl Serialize for ReductionOverhead

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.